McKinsey has estimated that hydrogen could account for one-fifth of the total energy consumed by 2050. In 2030 it is envisioned that over 10-15 million automobiles and 500,000 commercial vehicles could be powered by hydrogen. Liquid hydrogen is potentially very attractive for fuel delivery as well as on-board vehicle usage in the transportation segment. There are challenges today including...
A cryogenic expander for hydrogen liquefier with active magnetic bearings and an eddy current brake was designed and will be made and tested. The shaft design and strength review is very important factors for the turbine since it affects the performance and safety of the expander significantly. In order to product lower temperature hydrogen, the liquefier needs a very small and high-speed...
The numerical simulation included solid blades with four different leading-edge thicknesses and four different leading-edge geometries. One of the geometries was square, one was ellipse a(ellipse ratio is 1), one was ellipse b(ellipse ratio is 2), and the other was ellipse c(ellipse ratio is 3). The four thicknesses were 0.7mm, 0.6mm, 0.5mm, 0.4mm. The results show increased efficiency loss...
Cryogenic helium turbine expander is a core component of large helium refrigerators and liquefiers. Two-stage cryogenic helium turbine expanders are designed for 250W@4.5K helium refrigerator. One-dimensional design have been done based on the parameters calculated by the process. According to the geometric parameters calculated by the one-dimensional design, a new modeling method is adopted...
Absrtact: The influence of the number of grooves, the spiral angle, the groove depth, the ratio of length and width of spiral-groove thrust bearing on bearing capacity is analyzed by using fluent fluid computing software, and the influence of two new parameters---slope angle and internal spiral line---on load capacity of spiral-groove thrust bearing is also simulated, the parameters of spiral...
Most laboratory scale helium plants use pressurization of the storage Dewar to achieve the subsequent transfer of the liquefied helium. The unavoidable throttling in the transfer line in combination with cold gas displacement leads to high flash gas losses of up to 30 % of the transferred helium. Furthermore, filling rates are limited. A transfer pump in combination with a double-flow transfer...
Electric propulsion systems with MW-class output power density are expected to reduce fuel consumption of the current passenger aircrafts. In this scheme, motors and generators should have an output of 4000-30000 hp and capable of high-speed rotation. A high-temperature superconducting motor fitted with an adequate cooling system has the potential to achieve the requested efficiency and...
Robotic Refueling Mission 3 (RRM3) is an external payload on the International Space Station (ISS) to demonstrate the techniques for storing and transferring a cryogenic fuel, specifically methane, on orbit. The RRM3 Source Dewar was filled with ~19 kg (~42 liters) of liquid methane on October 28, 2018 and has been maintained with zero boil-off using a mechanical cryocooler since that time. ...
Growing interest in liquefied natural gas (LNG) as a rocket fuel necessitates a greater technical understanding of the compositional changes due to preferential boil-off (or weathering) that occurs during long duration storage. The purity of methane in LNG can range from 90 to 98%, and is subject to preferential boil-off due to its low boiling point compared to other constituents despite the...
Acceleration variation in low-gravity environment could significantly affect propellant slosh as well as thermodynamic behaviors inside cryogenic tank of vehicle upper stage. To realize reliable space management of cryogenic propellant, liquid-gas interface movement and deformation as well as associated pressure evolution during the slosh process should be understood previously. In the present...
The continuously rotational mechanism is one of key devices to holds a sapphire half wave plate (HWP) in a polarization modulator of a LiteBIRD satellite. Due to the system requirement, the HWP has to be kept at the cryogenic temperature while it is spinning. Thus, we employ a superconducting magnetic bearing (SMB) and AC synchronous motor, contactless rotational mechanism, to achieve the...
Rapid change in fluid flow conditions, whether purposeful or accidental, may result in the generation of a pressure spike in the fluid flow system followed by oscillations of pressure which is known as the fluid transient/fluid hammer. The maximum amplitude of these oscillations may go beyond the safe operating limits of the system producing detrimental effects on pipelines, valves, pumps and...
Simulations on self-pressurization and thermal stratification in cryogenic propellant storage tanks have been widely conducted in the literature. However, for the applications on orbit, the heat flux entering the tank could be non-uniform as the solar radiation angle varies, which may result in deviation of the behavior of pressurization and thermal stratification from regular conditions. That...
Ranque Hilsch vortex tube is commonly used with compressed air at atmospheric temperature for refrigeration purpose in various industrial applications. Literature shows that vortex tube can also be used as a potential device to separate compressed partially condensed air at cryogenic temperature into its main constituents – oxygen and nitrogen. When compressed partially condensed air is used...
Aerojet Rocketdyne’s 2033 Fast Conjunction Vehicle Concept to get to Mars is split into five segments: Deep Space Habitat, Inline Stages 1-3 and Core Stage. The three Inline Stages are propellant tanks carrying 19,205kg of liquid hydrogen (LH2). The Core Stage contains a smaller propellant tank of 14,084kg of LH2, a radiation attenuator and three nuclear thermal rocket engines. Each...
Our research group has developed a kW-class Stirling cryocooler. The Stirling cryocooler adopts a ‘gamma-type’ configuration operated with a linear compressor. The cold-end of the Stirling cryocooler is equipped with a heat exchanger that can accept and eventually liquefy natural gas (NG). The liquefied natural gas (LNG) is stored in an auxiliary reservoir. In this research paper, the...
This paper describes the cooling performance test of a free piston Stirling cryocooler accompanied by a double acting linear compressor. Although, the aforementioned Stirling cryocooler had originally been subjected to 77 K applications, i.e. liquid nitrogen (LN2), in this research, we have tried to figure out the cooling performance of the Stirling cryocooler operating above-110 K temperature...
In this paper, a high efficiency and low vibration stirling cryocooler has been designed and manufactured. The high efficiency compressor implementing the technology of dual opposed moving magnet motor and flexure bearing has been optimized to drive pneumatically a stirling cold finger also implementing flexure bearing technology. Through theoretical study and experimental study, the...
The Vuilleumier (VM) cycler was first invented in 1908 and the Vuilleumier-type (VM-type) cryocooler has been developed over 100 years up to now. The VM-type cryocooler is driven by a thermal compressor and it inherits the advantage of compactness and high theoretical efficiency from the traditional Stirling-type cryocooler. It has been a current hotspot in regenerative mechanical cryocooler...
The double stage Vuilleumier type pulse tube cryocooler (VM-DPTC) is a novel kind of 4K-class pulse tube cryocooler driven by thermal compressor. Besides its compact size and low-frequency working pattern eliminating the moving parts in cryogenic temperature (<77K) will improve the working stability and reduce the inherited losses. To design a proper 4K double stage pulse tube cryocooler under...
Effective storage and transfer of fluid commodities such as oxygen, hydrogen, natural gas, nitrogen, argon, and others is a necessity in many industries and for hosts of different applications. Molecules are typically contained as low pressure, cryogenic liquids; or as high-pressure gases. Liquefied gasses afford high energy and volume densities, but require complex storage systems to limit...
The removal of excess CO2 from natural gas to levels as low as 50 ppm is essential for the safe and reliable operation of liquefied natural gas (LNG) transport and delivery systems. Current chemical purification techniques, which are suitable for large processing plants, might not be suitable for small or mid-size plants which are expected to operate in future LNG delivery networks. The...
The large scale and efficiency of air separation units remain key barriers towards modular, distributed liquid oxygen systems. Identifying new physical separation mechanisms, or novel combinations of established methods, could enable the development of smaller, more modular air separation systems. In this paper we investigate the combination of centrifugal separation with paramagnetism of...
Dewars are used to store and transport cryogens like LNG, LN2, LOX, LHe etc. These comprise two vessels, one placed inside the other and held together either at the “neck” (input/output port) or by support systems, depending on the capacity, the mechanical loads on the vessel and the boil-off characteristic of the stored cryogen. Support system based dewars are more common for real-life and...
Carbon dioxide (CO$2$) is the main contributor to greenhouse gases (GHG). Cryogenic carbon capture is a potential alternative for systems with higher CO$2$ concentration. These methods do not involve the use of any chemicals (like solvents, adsorbents etc.) or supports (like membrane), so that the costs of raw materials and/or their regeneration are done away with. Desublimation is one of the...
The European Spallation Source (ESS) is a neutron-scattering facility being built with extensive international collaboration in Lund, Sweden. Three cryogenic plants with a vast cryogenic distribution system meet the cooling requirements of the superconducting RF cavities in the accelerator (ACCP), the cold hydrogen moderators in the target (TMCP), a cryomodule test stand and the sample...
Another neutral beam injector (NBI-2) was added for the KSTAR plasma experiments, recently. It requires a deuterium gas cryo-condensation system with the pumping speeds over one million liter/sec. For this purpose, many cryo-panels and a liquid helium cryogenic system were designed and constructed take into accounting the previous NBI. After the independent performance tests of the NBI-2, it...
The “CFETR integration engineering design” project and the program to develop an “integrated research facility for key systems of fusion reactor” have been granted by China in 2017. For the CFETR cryogenic system, an engineering conceptual design will be accomplished in 2020. The cryogenic system heat load is being calculated basing on the updated parameters of CFETR: a major and minor radius...
China Initiative Accelerator Driven System (CiADS) is a high-power nuclear waste processing research facility being built at huizhou, Guangdong, CHINA. CiADS consists of a 2.5 MW superconducting proton linac with energy of 500 MeV and 5 mA, a liquid lead bismuth eutectic (LBE) cooled fast reactor with 10 MW, and a granular flow target employed to coupling the accelerator and the sub-critical...
Large scientific facilities applying HeII technologies usually use the Joule-Thomson expansion for the final production of saturated superfluid helium at their cryomodules or magnet cryostats. Required cooling power is usually delivered by the flow of subcooled liquid helium flow at
4.5 K and 3 to 4 bar(a). Then, the 4.5 K helium is precooled in a heat exchanger and throttled to a...
The Advanced Photon Source Upgrade includes four 4.8-m long superconducting undulator (SCU) cryostats, each containing two up to 1.9-m long planar undulator NbTi magnets. The cooling is provided by six cryocoolers arranged in three thermal circuits. The magnets are indirectly cooled with LHe penetrating through channels in the magnet cores. This 4-K circuit which also includes a LHe tank, is...
The Advanced Photon Source (APS) is in the midst of a major facility upgrade consisting of a new electron storage ring (SR) and many new insertion devices (IDs) which will provide x-ray photon beams to a new suite of experimental end stations. Included among the new IDs are four 4.8-meter superconducting undulator (SCU) cryostats, each containing two 1.9-meter planar undulator magnets...
A superconducting multi-coil magnet system has been designed, analyzed and optimized, serving as demonstrator for a high filed Magnetic Resonance Imaging (MRI). This work focuses on the design and optimization of superconducting magnet, cryogenic cooling and cryostat systems.
The NbTi magnet system with multi-coils design has been optimized by balancing magnet performance, stability and...
The 1 MW HTS induction heater has developed for the non-ferrous metal industry where the HTS coil is used to generate a static magnetic field. The HTS magnet is made of YBCO conductor produced by Shanghai Superconductor, and the prospected operating temperature is about 25 K. The conduction-cooled HTS magnet consists of three solenoid coils wound with 18 km YBCO conductor. The inner and outer...
At present,Ultra-high field MRI system is considered the right way to explore the human brain because of the brain activity would be seen at a resolution of hundreds of micrometers. In 2017,the Chinese government launched an ambitious project to design and manufacture a 14T MRI system in object to neuroscience research in future.The superconducting magnets made of Nb3Sn superconductor and NbTi...
Studies suggest that an insulated ReBCO tape solenoid coil that is well-coupled inductively to shorted secondary can effectively be quench protected by discharging the coil across a constant voltage resistor. The discharge voltage across the constant voltage resistor is much lower than it would be for a constant resistance resistor that is used to achieve the same final quench temperature...
The HL-LHC Project currently undertaken by CERN that provides an upgrade to the existing LHC accelerator, is designed to increase the luminosity of the colliding particle bunches by a factor of at least five.
Part of this upgrade will require the replacement of the existing groups of three superconducting LHC triplet magnets situated on each side of the ATLAS and CMS detectors with similar...
In the frame of the HL-LHC project, innovative technical solutions are sought to measure accurately the position of the magnet cold mass inside the cryostat. To this end, a system based on laser-interferometry is being designed to monitor the displacement of the cold mass through dedicated openings in the new HL-LHC cryostats.
In order to test such a system on a full-scale setup in...
SuNAM’s RCE-DR (Reactive Co-Evaporation by Deposition and Reaction) process has been proved to be a high-throughput, cost-effective production method for the deposition of superconducting layer for coated conductor(CC). We showed that higher than 1 kA/cm-width critical current tape can be produced routinely, though our standard product comes with 700~800 A/12 mm-width only because we care for...
In order to overcome the narrower deposition windows and less longitudinal homogeneity for high in-field performance BaMO3 (M : Zr or Hf etc.) doped REBCO film, we applied hot-wall type pulsed-laser-deposition (PLD), which realized quite homogeneous crystalline growth conditions for REBCO by furnace-like substrate heating without spoiling productive throughput.
We studied growth...
Recently, in response to the growing demand on 2G HTS wire, both internal and external, the SuperOx group of companies has increased its production capacity, bringing it in 2018 to 120 km of 12 mm wide wire per year. Another incremental increase is planned in 2019.
As the fabrication technologies of 2G HTS wire have become more mature over the few last years, the key product development...
The three major types of mechanical cryocoolers in aerospace applications, namely reverse-Brayton cryocoolers, Stirling/pulse tube cryocoolers and Joule-Thomson cryocoolers, have significantly different performance characteristics. Some of these differences are due to the nature of their thermodynamic cycles; others come from their drastically differences in mean operating pressures and...
The European Spallation Source (ESS) is a neutron-scattering facility being built with extensive international collaboration in Lund, Sweden. The world’s most powerful linear proton accelerator shoots protons against a rotating tungsten target where neutrons are knocked off (“spallate”) and are guided to the neutron instrument suites. Three cryogenic plants and a vast cryogenic distribution...
There are three parts of the gas moving through the pulse tube of the pulse tube cryocooler, part I is the gas moving between the cold heat exchanger and the pulse tube, part II is the gas oscillating in the pulse tube all the time, part III is the gas moving between the pulse tube and the warm heat exchanger. The part of the gas that always moves in the pulse tube acts the same function of a...
Binary and ternary ZrO2-doped tube-type Nb3Sn wires were prepared by Hyper Tech Research Inc. for this study to investigate the effect of nanoparticle doping on the wire performance, with the aim of reaching the FCC 16T dipole-magnets requirements. The specimen, monofilamentary and multifilamentary wires, were characterized by magnetisation measurements in order to evaluate their critical...
THEVA developed an all PVD approach for the production of GdBCO based high temperature superconducting wires for a variety of applications. Using our pilot production line in Germany, we can manufacture the wires in long lengths with a critical current of 500 A/cm (77 K, 0 T) and more.
In order to increase the current density for magnet applications, we recently developed a new type of HTS...
Additive manufacturing is recognized as a potential technology to design and create complex geometries as well as a fast track to build prototype components. Different materials are possible to use, depending on the specific requirements of an application. Superconducting applications like magnets or rotating machines are demanding for the structural components. Either high and/or cyclic...
There is an increasing need for compact, low-mass, long-life cryocoolers for Earth science, deep space, and astrophysics missions. Packaging a cryocooler within a CubeSat is challenging, and many deep space missions have extreme environmental conditions, such as exposure of “warm” hardware to cryogenic temperatures, and exposure to very high levels of radiation. Lockheed Martin’s...
With end of year 2018 the LHC has completed its second physics run and started its second two-years long shut down period dedicated to planned consolidation, maintenance and upgrade activities. The run2 – four-year physics operation period started in spring 2015 – was used mainly for luminosity production but also to allow the optimization and adaptability of the cryogenic system capacity to...
Pneumatically-driven displacer mechanisms are widely used in Gifford-McMahon (G-M) cryocoolers. Particularly for large size G-M cryocoolers, this type of drive is preferable compared to the scotch yoke type, as only a small motor is required for driving the rotary valve and, therefore, the entire cryocooler can be very compact. Though various numerical models of G-M cryocoolers have been...
Nb3Sn is a low-temperature superconductor that had been believed to have very limited room for further improvement. However, the development of Nb3Sn wires with artificial pinning centers (APC) in recent years shows that Nb3Sn conductors can still be significantly improved. The most recent APC wires, in which Nb-Zr is internally oxidized to form ZrO2 particles, have achieved non-Cu Jc values...
Nitronic 40 forged tubes are typically used for structural reinforcement in high field pulse magnet design and applications. To better understand the mechanical performance of this versatile high strength austenitic steel a series of mechanical tests were conducted. Tensile were performed at 295 K, 77 K and 4 K, and cryogenic fracture mechanics tests were performed at 77 K and 4 K. The effect...
The Mapping Imaging Spectrometer for Europa (MISE) instrument on the Europa Clipper mission will use a Lockheed Martin “high power” Micro1-2 pulse tube cryocooler with a heat rejection temperature below 250 K. This paper describes the performance testing and results of Lockheed Martin Micro1-2 coolers optimized for these conditions. The thermal performance of two microcoolers was measured in...
Brookhaven National Laboratory operates the only functioning collider in the United States – the Relativistic Heavy Ion Collider (RHIC). The electron-ion collider (eRHIC) at Brookhaven National Laboratory (BNL) is a proposed large scale upgrade to the existing RHIC facility and is currently in its R&D phase. The new machine involves the use of superconducting technology for accelerating and...
Regenerators are key components of pulse tube cryocoolers and losses in regenerators have a significant effect on the performance of cryocoolers. In previous studies, the efficiency of regenerators have been characterized mostly based on the first law of thermodynamics, and second-law analyses have been based on exergy considerations or irreversibility associated with macroscopic flow...
Hyper Tech has developed the tube type strands with and without artificial pinning center (APC). For the regular tube type strands, our standard conductor with 217 filament arrays have been generated with 12 T non-Cu Jc values of about 2400-2500 A/mm2 with filament size of 35 micros at the 0.7 mm strand. We also made 547 filament conductors with 12 T non-Cu Jc values of about 2000-2200 A/mm2...
I will introduce the activity of RE-123 Coated Conductor (CC) at Shanghai Superconductor Technology Co. Ltd (SSTC). Recently we have many HTS projects in China including accelerator, high-field magnet, electric power applications and so on. For these projects, we have been supplying a large amount of RE-123 CC stably. The CC fabrication process is PLD-IBAD method and the Ic (77K, 0T) is around...
The Joint Special Design Team for a fusion demonstration reactor (DEMO) was organized in 2015 to enhance Japan’ s DEMO design activity and coordinate relevant research and development (R&D) toward DEMO. The fundamental concept of DEMO and its key components were already reported with main arguments on the design strategy [1]. Development of cryogenic materials with higher strength for toroidal...
Northrop Grumman Aerospace Systems (NGAS) has expanded its cryocooler product line with the introduction of the Mini Cooler Plus. The NGAS Mini Cooler Plus is a split cooler with a coaxial cold head connected through a transfer line to a vibrationally balanced back to back linear compressor. The mini compressor plus is designed for Space and non-Space applications. It is scaled from NGAS...
Compactness of linear accelerator is significant factor in achieving short construction times, low infrastructure and operation costs, and is considered as one of key parameters for the next accelerator generation. Operation of XFEL and other accelerators shows the possible limitations on present technologies related to the RF power operation inside the cryomodules. The next development steps...
The space-cycle averaged Nusselt number is used to characterize the heat transfer process of cold end heat exchanger in cryocoolers working with cryogenic helium oscillating flow. An experimental setup for cryogenic oscillating flow heat transfer measurement is designed and established to simulate actual operating conditions of cold-end heat exchanger of a regenerative refrigerator. The...
Nb3Sn conductors have been made which incorporate ZrO2 artificial pinning centers (APCs) that serve to refine the grain size of the superconducting material. Work on these wires has resulted in conductors which approach the FCC specification of Jc of 1500 A/mm2 at 16 T and 4.2 K. Understanding the causes of high Jc at mid to high...
A friction stir welding takes advantage of elimination of solidification cracking, liquation cracking and porosity associated with fusion-based welding techniques. In the present work, aluminium alloy 2219 in temper T62 (solution treatment and artificially aged), which finds many cryogenic applications, was jointed with friction stir welding techniques. The mechanical properties in terms of...
The Ricor K508N is an upgraded version of the K508 that has extensive flight heritage. This paper reports performance and exported force results for the COTS K508N as well as a K508N filled to a higher fill pressure with a high frequency motor. A comparison is made between the results of the K508N coolers and the K508 to determine their suitability for cooling on CubeSat missions. In addition,...
During the LHC (Large Hadron Collider) Run 2 between 2015 and 2018 inclusive, significant dynamic heat loads have been generated and successfully managed by the LHC cryogenic system. These dynamic heat loads are generated by several physical phenomena occurring at two temperature levels and with different time constants. On the magnet cold-mass maintained at 1.9 K, dynamic heat loads are...
Recent advances in Nb3Sn to meet the very demanding FCC specification of Jc greater than 1500A/mm2 (4.2K, 16T) has led to the development of an Nb-Ta-Hf alloy, which has indicated high layer Jc’s of 3700A/mm2 are possible. This high Jc translates to a non-Cu Jc of 2200A/mm2 in an RRP® configuration. The reason for this high Jc (16T,4.2K) is because the irreversibility field of (Nb-Ta)3Sn is...
In our previous study, we demonstrated that the reel-to-reel scanning Hall probe microscopy (RTR-SHPM) has a good advantage on the measurements of spatially resolved in-plane Jc distribution in a long length HTS tapes with a high spatial resolution along the tape width as well as the longitudinal direction. This is inevitable for a detection of localized defect in the tape, evaluation of an...
Abstract
Hiperco 50A is a highly desired material for use in cryogenic applications, specifically for adiabatic demagnetization refrigerators (ADRs) due to its magnetic field shielding capabilities. Although the alloy has good strength, there is a concern with the material’s brittle behavior which is believed to worsen at low temperature based on previous tests. The testing described here...
The explosion in SmallSat and CubeSat deployments has led to a need for miniaturized cooling solutions for sensors that require cooling. Since there are limited opportunities for miniaturization in the thermal mechanical unit (TMU) portion of the cryocooling system, much of the pressure to reduce size falls on the cryocooler control electronics (CCE). In the world of digital electronics,...
The High-Entropy Alloy (HEA) CoCrFeMnNi, an fcc alloy has been shown to exhibit remarkable properties at cryogenic temperatures, including high toughness as well as an increase in both yield strength and ductility as temperature is decreased to 77 Kelvin. A considerable number of applications require materials with such properties down to 4 Kelvin. For example, liquid hydrogen storage tanks...
Epoxy resin plays an important role in the layer insulation of superconducting magnets. The quench phenomenon associated with superconducting magnets often leads to excessive interlayer voltages, which can cause electrical aging of insulating materials. In this paper, tests were conducted to study the tree aging in epoxy resin/BN nanocomposites at 77 K under AC voltages. An experimental...
Compact Accelerator-driven Neutron Sources (CANS), such as the future High Brilliance Neutron Source (HBS), represent an efficient and cost-effective means to provide neutrons for scattering experiments. CANS have a lower neutron production compared to current reactor- or spallation-based neutron sources. However, CANS enable a holistic optimization of the neutron production chain and thus can...
For some years now, massive problems are often occurring when operating standard flow cryostats with pumped liquid helium. There are a large number of reports from various parts of the world, describing blockage problems arising typically within a few hours. Standard equipment for measuring the physical properties at temperatures below 4K is massively affected.
Hydrogen contaminations...
3D printed composites have excellent potential to satisfy needs for lighter and more complex cryogenic materials for aerospace, medical, and other sectors. However, few material property measurements are available. To address this need, this work performs ultimate tensile strength testing of 3D printed thermoplastics immersed in liquid nitrogen at approximately 77 K. Materials tested include...
The work presents the design and validation of a novel cryogenic-compressed hydrogen (CCH2) storage and supply system. This CCH2 system is designed to operate at the pressure up to 20MPa and temperature down to 20K. It is developed to provide an efficient and stable approach to storage and supply hydrogen for heavy trucks, powered by fuel cell stacks. The core strategy of process design and...
In this work, the implementation of residual strains in epoxy resin during its curing process with an operational range of 300 K-400 K and cooling process with an operational range of 15 K-300 K was studied using embedded strain gauges. This represents a significant reduction in the lowest usable temperature of epoxy resin as well as a significant increase in sensitivity of residual strains in...
A heat switch originally developed by ESA/Twente has been modified for use with superfluid helium in the 1 K temperature range as part of a variable temperature insert in an NMR type magnet system. The key challenge was to develop a process that allows to removably contact the additively manufactured switch to a copper surface with nearly no temperature gradient build up. The experiments at GE...
The performance of the internal purifier has a direct impact on the liquefaction capacity of the helium liquefier. With increasing impurity level in helium, liquefaction capacity of the helium liquefier reduced significantly. In order to ensure the helium liquefier operates safely and stable, remove the impurities from the helium in the helium liquefier and improve the utilization of the...
Purification systems are necessary to support commissioning and operation of helium refrigeration and associated experimental systems. These systems are typically designed for a low level of impurity (i.e., in parts per million), since a 4.5 K or 2 K helium system will freeze out every other substance. The trace impurities can block and/or change flow distribution in heat exchangers and...
Helium is an expensive consumable in cryogenic facilities and is used widely in space, medical and energy research. In NSRRC, liquid helium is used as a coolant for cooling superconducting magnets and SRF cavities. Minor contaminants such as nitrogen, oxygen, moisture and oil will be picked up when liquid helium circulates in the large scale cryogenic systems, these contaminants will...
The principal design requirement of cryogenic systems used for liquid argon neutrino detectors is ultra-high purity. The primary impurities that affect operation of the detector are electronegative types such as oxygen and water, or light quenching varieties such as nitrogen. It is the electronegative property of oxygen and water that causes reduced rates in the detection of neutrino...
One, of two, 850,000 gallon liquid hydrogen storage spheres, at NASA’s Kennedy Space Center, was decommissioned in 2010. This tank had an abnormally high heat leak that was investigated and determined to be the result of a large void in the perlite insulation. The insulation void was subsequently filled, and the tank was refurbished for its planned use in the Space Launch System (SLS)...
Fermi National Accelerator Laboratory (FNAL) is developing the international Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) to advance neutrino science. The flagship of the DUNE project consists of a large particle detector constructed one-mile (1.6 km) beneath the surface at the Sanford Underground Research Facility (SURF) in Lead, SD. The SURF detector...
The NIST Center for Neutron Research (NCNR) operates a 20 MW research reactor that produces neutrons for a suite of 30 neutron scattering instruments. 70% of these instruments use cold neutrons (E < 5 meV), which are moderated by two separate cold neutron sources. The cold moderator for both sources is liquid hydrogen (LH2), which is in turn cooled by a recently commissioned 7 kW, 14K helium...
Superfluid cryogenics systems at KEK are constructed for research and development of cryomodules of the compact Energy Recovery Linac (cERL) and International Linear Collider (ILC). The niobium superconducting radio frequency (SRF) cavities in the cERL and ILC, operate at temperatures of 2.0 K or below. The SRF cavities are cooled with saturated superfluid helium, which is another phase of...
It has always been a research hotspot to improve the overall efficiency of pulse tube cryocooler and the regenerator as the core component of the pulse tube cryocooler directly determines the performance of the overall machine. Therefore, an approach of improving the efficiency of the whole machine has been provided as improving the performance of the regenerator. This paper is based on a...
The multi-bypass is one of the effective ways to reduce the lowest no-load temperature of pulse tube cryocooler. The common structure of multi-bypass is to use a thin tube to connect the middle of the pulse tube to the middle of the regenerator which can reduce the mass flow through the regenerator and adjust the phase angle of the cold end for the refrigerator, which effectively reducing the...
Abstract:The regenerator is the core heat exchange component of the Stirling engine, and the structural form and physical properties of the filling material are the vital important factor determining its performance. In this paper, a three-dimensional model of the regenerator is established using Ansys' fluent module to simulate the regenerative flow in the alternating flow. The property of...
To reduce the volume of hydrogen or helium cryogenic refrigerator and
liquefaction, we need the minimum volume to achieve the efficiency and the
pressure loss of the plate-fin heat exchangers given by the process. For
this purpose, this paper presented a new comprehensive performance factor
S = J^3As^2/(fV^2), which means ε/(∆p·V_{eff}) or ε/(w_{pump}*V_{eff}). Based on the performance...
The regenerator is a key component of a pulse tube cryocooler, and is also a major contributor to irreversibility and losses in the cryocooler. In this study a method for the assessment of losses in cryocooler regenerators based on entropy generation is proposed. Pore-level CFD simulations are performed for woven mesh regenerator filler by defining periodically repeating unit cells....
Practical applications of high temperature superconductors (HTS) usually demand long length wires in which the materials are inevitably polycrystalline. The critical temperature at 38 K and the high upper critical field around 90 T make K-doped BaFe2Fe2 (Ba122) attractive as a high field conductor. The last key aspect which needs to be demonstrated is high Jc in polycrystalline forms such as a...
Single crystals of Ba(Fe1-xNix)2As2 have been produced for systematic magnetic measurements of the critical current density (Jc) over a range of dopings from
x=0.025 to 0.066 and a range of temperatures from 2 K. Analysis of the field dependent critical current density, Jc, shows strong evidence pointing to a flux pinning mechanism dominated by local variation in the mean free path for all...
Cold high pressure densification (CHPD) at pressure up to 1.5 GPa was used to enhance the critical current density (Jc) and connectivity of the in situ powder-in-tube (PIT) and hybrid MgB2 strand. First, the improvement of longitudinal and transverse magnetic Jcs were observed at 4.2 K and 10 K for PIT strands. The higher longitudinal and transverse connectivity in densified strands is shown...
It has been shown experimentally that the stoichiometry of a superconducting magnesium diboride having AlB2 structure with a high level of superconducting properties (transition temperature to superconducting state, critical current density, upper critical magnetic field, and field of irreversibility) is close to MgB1.75O0.25. The ab-inito simulation confirmed the possibility of the existence...
As practical applications of bulk superconductors grown by TSMG and similar methods draw closer it has become apparent that close attention needs to be paid to the mechanical, as opposed to superconducting, properties of these materials. In particular the key limiting factor to the trapping of further increased magnetic fields in bulk superconductors appears to be their mechanical...
The performance of a high temperature superconducting (HTS) magnetic bearing is directly related to the external magnetic field of the permanent magnet (PM) rotor and properties, such trapped magnetic flux, of the superconducting stator. In this paper, finite element models are built for square, tile and circular shape high temperature superconducting blocks of different sizes. A...
Next generation fusion and high energy physics machines will require high field magnets with the ability to operate at variable temperatures. Therefore, high current cables able to operate in such conditions will be required. As reaching magnetic fields higher than 16 T using traditional Low Temperature Superconductors can be challenging, the more recently investigated High Temperature...
In the quest for ultra-high-field magnets, one inevitable challenge is ever larger electromagnetic forces and their effect on the conductor. REBa2Cu3O7-x (REBCO) coated conductors have extraordinary transport and mechanical properties but how the vortex pinning and the external stresses are related is not well understood, especially when it passes the reversible strain of the conductor. This...
In the HTS superconducting magnet application fields like motors, generators, and SMES, 2G REBCO coated conductor (CC) tapes will be subjected to alternating stress or strain during manufacturing and operation. In these applications, the repeated load affects the mechanical integrity and eventually the electrical transport property of CC tapes. Therefore, mechanical and electromechanical...
REBCO coated conductors are promising candidates for high field (>25 T) user magnets. However, as the demand for higher fields increase, so does the potential to overstrain the conductors being used. Coated conductor substrates, such as 310 stainless steel and the super-alloy Hastelloy C276, serve as the backbone for mechanical strength in these conductors. Both substrate alloys share similar...
High quality 2G HTS tapes are desired for power applications, cables, and high field magnets. The original tape is fabricated in 12-40 mm widths, but most magnets and many cables require narrower tapes made by slitting the original tape. There are many advantages of narrow tapes: reduced magnetization loss, improved field quality, faster ramp time, reduced cryogen loss, and the opportunity...
The development of coils which can survive a quench is a crucial aspect for demonstrating the viability of MgB2-based main magnet coils for MRI. Here we have studied the thermal stability properties of a large (outer diameter: 901 mm; winding pack: 44 mm thick × 50.6 mm high) conduction-cooled, R&W, MgB2 superconducting coil. Minimum quench energy (MQE) values were measured for different coil...
This paper summarizes the latest developments in some on-going research at the Wentworth Institute of Technology to qualify a new reinforced-2212 superconductor, being developed by Solid Materials Solutions in Chelmsford, MA, for use in high magnetic fields. Under an NIH-funded grant, we are developing a high-speed spin test which will impose circumferential hoop stresses on the 2212 windings...
A material microstructure in-situ analysis instrument was designed in which a scanning electron microscope and a small refrigerator were used to observe the microscopic morphology and cool the sample (can be cooled as low as 15 K), respectively. The instrument is also equipped with a deformation excitation device that can stretch and compress the material in situ. The vibration damping...
Epoxy/aluminum nitride composites (EP/AlN) with high thermal conductivity, low thermal expansion and excellent insulation characteristics are particularly suitable for protecting a superconducting power equipment from the permanent damage of temperature rise and internal stress in quenching process. In this work, micro/nano AlN particles were used as fillers to improve the thermal conductivity...
Recent results are reported in the development of 2-layer cable-in-conduit (CIC) that is designed for hybrid-coil magnets. The CIC preserves the full performance of the individual wires, and can be formed into flared-end windings for dipoles into layer-wound toroids and solenoids for hybrid windings for tokamaks. The structure of the CIC windings is designed to accommodate winding and...
We have magnetically modelled a fast switching, polarizing, superconducting undulator. The particular design is called the SuperConducting Arbitrarily Po-larizing Emitter, or SCAPE, It has a four jaw design, and produces LCP, RCP, L-H and L-V polarization states. This design uses a dual SC undulator scheme to achieve fast switching. Each undulator is preset to generate a fixed polarization...
Superconducting magnets are one of the superior contenders in achieving the targets of electric aircraft industry successfully as they have very high power densities compared to other battery storage systems. Many aviation research agencies are looking at superconducting magnets as one of the alternate in replacing the conventional jet engines completely (electric aircrafts) or partially...
Epoxy resin nanocomposites are widely used in high voltage direct current (HVDC) high temperature superconducting (HTS) power cable. In this paper, the DC flashover characteristics of ZnO/EP composites at both room temperature and 77K were studied. The samples were made by dispersing ZnO nanoparticles into EP resin with weight percentages of 0%, 1%, 3%, 6% and 10% respectively. The experiment...
Additive manufacturing in industrial and commercial applications has drastically changed manufacturing capabilities while expanding the materials available to cryogenic engineers. Unfortunately, the thermal properties of 3D printed materials and filled materials are not well characterized, especially at cryogenic temperatures. To fill gaps in the literature, an experimental system was...
Unlike the more common local conductance spectroscopy, nonlocal conductance can differentiate between nontopological zero-energy modes localized around inhomogeneities, and true Majorana edge modes in the topological phase. In particular, negative nonlocal conductance is dominated by the crossed Andreev reflection. Fundamentally, the effect reflects the system’s topology. In graphene, the...
The analysis of superconducting properties in the presence of spin-orbit coupling is the subject of many scientific papers published in recent years. Unfortunately, the understanding of the problem is insufficient due to the fact that the theoretical results have been obtained using too simple models.
The main purpose of the research is to derive full thermodynamic equations for...
In the framework of the Eliashberg formalism has, the tendency to create phonon – induced superconducting state at a square lattice was analyzed. We have shown unbalanced superconducting state can not be created. However, for unbalanced parameter value smaller than $γ_{C}=0.42$ the electron – phonon interaction may induce non – classical superconducting state – the thermodynamic functions...
In this work we will discuss several theories explaining the phenomena of negative magnetoresistance (magnetoconductivity) in diluted granular multilayers samples in insulating side of the Metal-Insulator Transition (MIT). These theories will be confronted with experimental measurements in order to try to provide physical explanations for these phenomena. We re-used in our modeling...
We study in this manuscript the low temperature dependence of the electrical resistivity in the insulating phase in both cases nearest neighbors hopping and variable range hopping in a holes system of high mobility in two dimensions hole gas grown on the surface (311) GaAs. The behavior of the resistivity in the insulating phase in quantum wells p-GaAs is qualitatively consistent with the...
High energy physics research facilities require a vast cryogenic infrastructure to cool superconducting magnets, superconducting RF cavities, and other components to their necessary operational temperatures. The temperature sensors used to monitor this infrastructure are invariably exposed to leakage radiation in varying doses depending upon their location. Compared to many other cryogenic...
High temperature superconducting (HTS) power cables are expected to be used in electric aircraft and ships that will have integrated power systems. There have been a few studies on understanding electrical faults in power systems consisting of HTS cables. However, there are no comprehensive studies on the response of HTS cables for various kinds of electrical faults. We have recently initiated...
When I joined Tachikawa's group in NRIM(now NIMS) in 1978, they have almost finished the research of bronze–process and they were carrying out many kinds of impurity additions to Nb3Sn wires. Soon they found that Ti addition is very effective to enhance Jc values at high field region. I measured Hc2 values of various impurity added bronze processed Nb3Sn wires at MIT, and found that Ti or Ta...
Coated conductors (CCs) of YBa2Cu3O7 (YBCO) have emerged as the most attractive opportunity to reach unique performances for large scale superconducting power applications and high field magnets, though reducing the cost/performance ratio continues to be a key objective at present. It is still particularly necessary to develop faster growth in order to increase the CC throughput....
The resin used for bonding and insulating superconducting magnets can be a major factor in ensuring reliable and stable operation of the completed assembly. There are many resin systems and available to magnet designers and engineers. The selection of the correct material depends on the application technique selected, the processing requirements and the end properties required of the cured...
Vacuum is the primary method for a thermal insulation of cold elements in cryogenic systems, tanks and other cryogenic equipment. A dangerous situation arise in the case of vacuum envelope failure when a 300 K air enters the vacuum and the cold elements of cryogenics equipment are exposed to a potentially intense heat fluxes and air velocity. Depending on a mass flow of the air (equivalent to...
Power systems in electric transportation applications and some power grids are being designed with medium voltage DC (MVDC) systems to achieve high power density and take advantage of the new developments in power electronics. The coaxial dipole superconducting gas-insulated line (S-GIL) is a high temperature superconducting (HTS) cable design which shows great potential to provide a high...
Superconducting Nb3Sn wires are actually in the focus to achieve enhanced high field performance, in particular for future advanced accelerator magnets of the next generation, by means of novel preparation methods to increase the flux pinning. It was learned already quite early in the development of the material that stresses and strains play an important role in the Nb3Sn system and strongly...
STI continues to improve our High Temperature Superconducting (HTS) ReBCO coated conductor production and metrology techniques to deliver higher-performance & lower-cost superconducting products to our customers in key application markets. In this talk, we’ll cover (3) areas of our recent focus to enhance our product qualities; Long length in-field metrology for 2G HTS characterization,...
In this talk, we will present magnet performance and quench training of LBNL Nb3Sn accelerator magnets and our experience and quests for a better epoxy for reducing quench training in Nb3Sn superconducting magnets. We will present our assessment of properties of CTD-101K, several other epoxies that have been used for superconducting magnets, and new recipes being explored at LBNL, and discuss...
Respiratory Protective Devices such as a self-contained breathing apparatus or a hose supplied breathing apparatus connected to a stationary source, are used by first responders during an emergency. The most common means to store air is in high pressure gas cylinders up to 7,500psi. NIOSH conducted research in conjunction with NASA to employ cryogenics as a more efficient, safer way of storing...
Superconducting radio frequency (SRF) cavities are traditionally cooled by immersion in liquid helium, which enforces building and operating complex cryogenic infrastructure. A simpler alternative for cooling the cavities is to conductively couple the cavities with closed-cycle regenerative cryocoolers. In this contribution, we will showcase the development of an experimental setup for...
The discovery that small amounts of Cu enable the formation of V3Ga, Nb3Sn and other A15 compounds without intermediate Nb-Sn phase formation without needing to go to liquid reactions opened the path to fine A15 grain size and multifilamentary strand and all the applications that followed, from NMR to ITER and beyond. Nb3Sn tape then rapidly disappeared. In order to meet the needs of the next...
The International Society for Sample Environment (sampleenvironment.org) has developed a device-communication protocol for shared pools of portable and interchangeable laboratory equipment, including temperature, pressure, and magnetic field systems. The Sample Environment Communication Protocol (SECoP) uses self-describing metadata to enable plug-and-play connection of a wide range of devices...
Any upgrade of the existing Relativistic Heavy Ion Collider (RHIC) to an electron-ion collider (eRHIC) at Brookhaven will employ superconducting radio frequency (SRF) cavities. These SRF cavities will be used to accelerate the electron beam in the new machine. External and internal mechanical, acoustic, electrical excitation sources, typically refered to as microphonics, cause disturbances to...
YBCO based 2G HTS wires are being manufactured at MetOx on pilot production scale at this time with the ultimate goal of providing the industry with high performance and low-cost wires for magnet and cable applications. MetOx uses IBAD/MOCVD process and currently coats 12 mm wide tape. At this time MetOx wires have 50 m single piece length and 77K/SF Ic of 400-500A. Two different recipes have...
B. J. Gold1,2, B. Auchmann2,3, D. Tommasini3, T. A. Tervoort1
1Soft Materials, Department of Materials, ETH Zürich, Zürich, Switzerland
2Paul Scherrer Institute, GFA, Villigen, Switzerland
3CERN, TE, Geneva, Switzerland
The Future Circular Collider Study (FCC, hosted by CERN) explores possible designs for circular colliders addressing the post-LHC era. To reach higher energies which is...
In the last decades, several laboratories, like CERN, DESY, CEBAF, constructed the accelerators with large number of superconducting (sc) cavities or magnets operating at 2 or 4K temperature levels. Other accelerators, e.g. at GSI/FAIR, SLAC, MSU, ESS are under construction. Typically, the operation of sc cavity requires narrower ranges of pressure variation than ones of sc magnets. For large...
High temperature superconducting (HTS) power transmission cables are cooled to operating temperatures typically below 80 K using liquid nitrogen or gaseous helium. HTS cables are being considered for use in connecting substations to allow transformers to share load, or for long distance, low loss electrical power transmission. One interesting feature of HTS cables is that they have been shown...
Prof. Kyoji Tachikawa always had strong interest for superconducting materials having high Jc in high magnetic fields. In 1980’s, his interests had moved from the bronze processed V3Ga and Nb3Sn wires to advanced Nb3Al and Nb3(Al,Ge) wires, which had much higher Bc2(4.2K) of over 30 T. The stoichiometric Nb3Al as well as Nb3(Al,Ge) required high temperature heat treatment about 2,000oC, so...
The Laboratory SBT has studied Fundamental Turbulence at High Reynolds Number for many years. Indeed, low temperature Helium has such a low viscosity, that very high values of the so-called Reynolds number Re≡UL/υ can be reached (U: velocity, L: characteristic scale of the flow, υ kinematic viscosity). These values allow to compare experiments with existing phenomenological descriptions of...
We report the use of a series of high-temperature superconducting leads in a cryostat that require no soldering to replace in the event of a failed lead. The temperature range spanned by the leads is 50 to 3 Kelvin and they typically carry currents up to 4 amperes although they have a much higher capacity in this temperature range. The leads are integrated into the cryostat by clamping both...
Dramatic improvement in in-field performance of thick 2G-HTS tapes has been recently achieved in >4 m thick REBCO films over a wide range of field and temperatures, as demonstrated by the resulting engineering current densities, JE, of over 15 MA/cm2 at 30 K, 3 T and over 5 kA/mm2 (0.5 MA/cm2) at 14 T, 4.2 K, which is over five times higher than that of Nb3Sn. The ability to control film...
Superconducting magnet epoxy impregnation has the unique requirement of utilizing a liquid with very specific properties at slightly elevated temperatures that transforms into a solid with low temperature property requirements. Here we test the properties of two neat resin epoxies at room and cryogenic temperatures. Tensile, compressive, fracture toughness and thermal expansion tests are...
The recent progresses, properties, and future work of APC Nb3Sn conductors are reported. Great progresses have been made in the past two years in developing the APC Nb3Sn wires, including adding Ta dopant and improving wire recipe and quality. This has led to great improvement in their properties. The most recent APC wires have achieved Bc2 (4.2 K) above 28 T (1-2 T higher than conventional...
The dimensioning of pressure relief devices (PRD) for cryogenic pressure equipment requires knowledge on the heat input at the maximum credible incident. In helium cryostats, this situation is typically defined by the loss of insulating vacuum (LIV), where the heat load is induced by desublimation and condensation of atmospheric air on the cryogenic surface. This surface is often covered with...
Current leads supply electrical energy from a room-temperature power supply to a superconducting application, representing thus a major thermal load. State-of-the-art cooling solutions use either open (vapor cooled) or multi-stage closed cycle systems. The multi-stage concept can be integrated in one cryogenic mixed refrigerant cycle (CMRC), where a wide-boiling fluid mixture absorbs the heat...
The construction of the Future Circular Collider (FCC) has very stringent requirements for Nb3Sn conductor critical current density, Jc, with a target non-Cu Jc(16T, 4.2K) of at least 1500 A/mm2. Nowadays the best commercial Nb3Sn strands can only reach 1300 A/mm2, consequently it will be necessary to significantly increase the...
The University of Houston and AMPeers have developed round REBCO wires of 1.3 to 1.9 mm in diameter that can retain nearly 100% of its critical current even when bent to a radius of 15 mm. Such a small bending radius is a requirement of canted cosine theta coils that are being developed for accelerator magnets. Such small diameter wires and excellent bend strain tolerance have been made...
Epoxy resins have long been a focus of superconducting magnet design. They provide strength and stability to the superconductor, to allow coil fabrication and consistent magnet performance. They are often cited as a main contributor to magnet performance, often as a limiting factor, from epoxy cracking and energy release. While a large variety of alternative thermoset resins have been...
As compared to cryogenic storage vessels, helium cryostats include active components such as superconducting devices, heaters, pumps and control valves, which strongly influence the risk of excessive pressure. The European Standard "Helium cryostats – protection against excessive pressure" is therefore being developed by the working group CEN/TC 268/WG6, dealing with specific helium technology...
The number of flights is growing each year by 5% and consequently its environmental footprint. Be it CO2-, NOx or noise emissions - the aviation industry is dedicated to hunt the demons of its own success and bring down them down by roughly 80 % until 2050. One broadly communicated and advocated way to achieve these goals is by means of electric and hybrid-electric propulsion. Without doubt,...
Vacuum break in particle accelerators is a major concern due to risks associated with personnel and extensive equipment damage. Continuing research in our lab focuses on the sudden loss of vacuum in the liquid helium cooled beam-line tubes of superconducting particle accelerators. In our previous research, we studied nitrogen gas propagation in a uniform tube system immersed in both normal...
The comprehensive research facility for key systems of fusion reactors was included in the “13th Five-Year Plan” priority project in China. In order to meet the requirements of cryogenic testing of the large superconducting magnets, it is proposed to build a 3kW@4.5K refrigerator and carry out research on 3kW@4.5K helium cryogenic system. To evaluate the reliability of the 3kW refrigerator,...
In mechanical experiments, the stirling cooler is often rigidly contacted with the fixture, and mechanical condition applied on the cooler is the same as that generated by the shaking table. In some special cases, flexible design is needed between the cooler and the fixture, and the relative position between them will change during the vibration process. Then, the mechanical condition on the...
Liquid natural gas (LNG) boiling process concerns majority of LNG applications because of a need of its regasification. Depending on pressure an equilibrium temperature of LNG is 112-160K. The low boiling temperature of LNG makes the vaporisation process complicated. An important risk of the regasification is related to a possibility of a solid phase formation (freezing of a heating fluid)....
Cryogenic fluids are used for wide range of industrial and laboratory applications. Vacuum or supper-insulated transfer lines are efficiently used to transfer these fluids from the storage Dewars to the end applications. As the heat transfer to the cryogens flowing through the transfer line cannot be completely eliminated, many a times two-phase flow occurs during the transfer process. It is...
The so-called FlexCryo is a new integrated instrumentation developed by CEA/DSBT and dedicated to cryogenic applications.
It can measure temperatures down to 50 mK using a lock-in amplifier and drive heaters from microwatts to watt.
This flexible solution is based on a 19 inch rack featuring a processor card and five slots.
Currently these slots can accept three types of cards following:
-...
Stable operation of helium cryogenic system and low heat loads are of paramount importance. In order to achieve the required pressure stability and heat loads, all sources of possible disturbances have to be eliminated at the design phase and latest during the commissioning activities. One of such disturbances is thermally driven oscillations (TAO), which could occur when a local heat source...
Cryogenic valves are indispensable components for the reliable operation and controlling of cryogenic facilities. The key controlling components are cryogenic valves, which are used to regulate the flow of cryogenic fluids or to liquefy gases. Helium cryogenics typically has additional requirements, for example, very low heat loads, high leakage tightness, etc, which leads to specialized...
Carbon dioxide (CO2) cryogenic desublimation separation is an emerging contamination-free carbon capture method. Solid CO2 as an important industrial product is widely used in many fields. So far, there have been few investigations focusing on the detailed desublimation characteristics of CO2 due to the difficulty of visual experiments under low temperatures and the challenge of controlling...
A novel fruit peeling method based on cryogenic treatment is proposed. And a corresponding cryogenic equipment has been developed. The principle of cryogenic peeling is that the expansion coefficient of fruit and peel is different at low temperature. Compared with the conventional chemical peeling methods, cryogenic treatment peeling is a treatment method that does not contaminate foods. For...
Hybrid J-T cooler has been the most commonly used 4K cryocooler in space detectors. Although resistance of the J-T valve deeply affects the performance of the J-T cooler, few researches have been down especially on the J-T orifice. Because the J-T process is quite complicate, the dimensionless resistance coefficient is defined and deduced using dimensional analysis method to evaluate the...
Future astrophysics missions such as SPICA, Athena or LiteBird will need a cooling down below 1 K (until 50 mK) to achieve the detectors required sensibility. To address such requirements, cooling chains are build coupling several technologies using intermediate temperatures cooling.
A high cooling power at 15 K is then essential, so the CEA-SBT designed a Pulse Tube cooler system providing...
Miniaturized cryocooler systems are among the key components of state-of-art infrared sensing small satellites (SmallSats). To achieve small size, these cryocoolers need to operate at high frequencies, e.g., 200 to 300 Hz range. High frequency leads to lower compression and expansion swept volumes and hence a smaller cryocooler. Previously we showed that pulse tube cryocoolers have high...
Shanghai Institute of Technical Physics (SITP) of the Chinese Academy of Sciences (CAS) has been engaging in the development of space long-life cryocooler for over 30 years. The three typical cryocooler (pneumatic Stirling cooler, Stirling cooler and pulse tube cooler) were all developed simultaneously. In 2002, a self-developed pneumatic Stirling cryocooler operated in orbit successfully in...
This paper presents the design and performance test of a single stage coaxial pulse tube cryocooler operating at 80 K using a moving magnet type linear compressor. We designed the compressor with the input capability of 100 W at the operating frequency of 50 Hz. A pulse tube cold finger with a double segmented inertance tube was designed for the cooling capacity of over 1.5 W at 80 K. The...
The cryocoolers working around the liquid nitrogen temperature have important applications in high temperature superconducting, infrared detectors and gas liquefaction. Meanwhile, high frequency pulse tube cryocoolers have attracted the attention of scholars due to low vibration, compactness and high reliability. This paper developed an 20W/80K high frequency pulse tube cryocooler with...
High-frequency pulse tube cryocooler is difficult to obtain lower cooling temperature: to obtain the liquid helium temperature, three-stage or four-stage structure by thermal coupling are currently used. In order to further improve the compactness, a two-stage gas-coupled high-frequency multi-bypass coaxial pulse tube cryocooler has been designed. The simulation results indicate that the...
The new Cryogenic Flux Capacitor (CFC) technology employs nano-porous aerogel composites to store large quantities of fluid molecules in a physisorbed solid-state condition at moderate pressures and cryogenic temperatures. By its design architecture, a CFC device can be “charged” and “discharged” quickly and on-demand according to standby/usage requirements. One of three main application areas...
A mobile Magneto encephalography (MEG) of Sumitomo Heavy Industries, Ltd. (SHI) uses a high temperature superconducting magnetic shield, Superconductor-Normal-metal-Superconductor (SNS) type Superconducting Quantum Interface Device (SQUID) sensors, and they are cooled by a zero boil-off cooling system. The zero boil-off cooling system consists of a circulating cooled helium gas system for...
We performed magnetic, mechanical, and thermal modeling of a 3T, actively shielded, conduction-cooled, whole-body MRI magnet. The design had a magnet length and conductor length comparable to NbTi helium-bath-cooled, 3 T designs. The design had a magnetic field homogeneity better than 10 ppm within a DSV of 49 cm. A new class of MgB2 strand especially designed for MRI applications was...
Cryo-ablation is a breast cancer treatment method that utilizes a small probe in precise locations within the body to freeze and destroy unwanted cancer tissue. Recently there has been a growing interest in combining cryo-ablation with magnetic resonance imaging (MRI). The challenge of combining these two technologies is that MRI devices require the absence of metals, and traditional heat...
In order to further maintain the quality of sea-fish after harvest, it is necessary to figure out the heat transfer law during its cryogenic freezing and cryopreservation process (below -40℃). There is little literature to discuss thermo-physical properties of food in cryogenic temperature. In this paper, the thermo-physical properties of sea-fish were measured experimentally. A special cold...
Golden Pomfret is tender, delicious and rich in nutrition, but is also apt to deteriorate. Cryogenic quick freezing technology is applied to offer a fast freezing rate to maintain the quality of Golden Pomfret. The freezing rate depends on the freezing process temperature and gas flow rate in the cryogenic freezer. In order to achieve a sufficiently high freezing rate, numerical calculation...
This work describes the methods for transporting cryogens through single- or multichannel pipelines. It also presents examples of the use of cryogenic lines and of their designs, referring in detail to typical structural nodes found in cryogenic pipelines. The second principle of dynamics and the Gouy-Stodola theorem are discussed from the perspective of their application in optimizing and...
Multiple bubble interaction in initially quiescent liquid, under certain conditions, is accompanied by the generation of jets, shockwaves, and light. At cryogenic temperature (< 123 K) when certain materials become brittle, such afore-mentioned physical effects can be effective in disintegrating them to smaller fragments under controlled erosion. The spatial and temporal-scales of such...
To study the dynamically changing interfacial structures due to the collapse of the cavitating bubble, and the mechanism whereby forces large enough to cause damage are brought to bear against a rigid wall is of great importance in the study of cavitation induced erosion, and, still somewhat obscure in cryogenic liquids. Study of individual collapsing bubbles and resulting microjet during the...
Storage of cryogenic propellants in rocket fuel tanks gives rise to an undesirable phenomenon called thermal stratification. Large temperature difference between the cryogen and ambient results in significant heat leakage into the tank. The liquid near the walls heat up and flow to the interface due to natural convection giving rise to an axial temperature gradient inside the tank. Maintaining...
With the growing concern of environment problems, there are urgent demands for environment-friendly refrigerants in the refrigeration industry. As a natural refrigerant, Methane (R50) has zero ozone depletion potential and quite low global warming potential. What’s more, it is also the major cryogenic refrigerant of the Mixture Joule-Thomson Refrigeration cycle (MJTR). Therefore, accurate...
Computational simulations of superfluid helium are needed in order to improve the design of the cooling system of superconducting magnets in particle accelerators and to achieve a better understanding of the transient phenomena during magnet quenches. A conjugate heat transfer numerical model based on the C++ toolbox OpenFOAM is implemented to three-dimensional case studies involving...
In this paper, a set of dry vacuum pumps suitable for a 500W @2K helium refrigerator were investigated. Process flow diagram and the control strategies of a set of dry vacuum pumps were designed. The Experiments including the mass flow rate and pressure ratio of a set of dry vacuum pumps with the air and helium gas were tested. The input pressure of 40 kPa and output pressure of 1.05~1.1 bara...
The Korea Superconducting Tokamak Advanced Research (KSTAR) has been operated for the basic research of fusion energy and its 11th campaign was performed in 2018. It was necessary to construct new cryogenic facility in order to operate the KSTAR ancillary system for the advancement of KSTAR plasma performance. The KSTAR Upgraded HElium supply System (UHES) was constructed in 2016 which is...
There is growing evidence showing that the cold compressors in the Modified Sub-atmospheric Cold Box (SC1/SCM) of the JLab Central Helium Liquefier (CHL) are approaching the end of their life. Their replacement parts are no longer available due to obsolescence, thus placing the Physics program at serious risk. A new sub-atmospheric cold box (SC1R), which hosts five technologically superior,...
Commissioning of the LCLS II cryogenic plant has been planned with respect to electrical and mechanical systems checkout, equipment cleanup, cool-down, and individual performance evaluation. This plant consists of warm and cold storage, helium compressors, 4.5 K and 2 K cold boxes, and all auxiliaries typical for helium refrigeration processes. The 2 K cold box, consisting of five cold...
Within the conceptual design study for the Future Circular Hadron Collider (FCC-hh) it was shown, that a large part of the total cryogenic heat load falls into the 40 to 60 K temperature level. Thus, additional cryogenic refrigerators for this temperature level are specified for each of the 10 foreseen cryoplants. Such cryogenic system was developed at the TU Dresden and is based on a Brayton...
A dynamic simulation of a medium-sized hydrogen liquefier has been proposed using process simulation software EcosimPro. A helium refrigerator with one turbine provides cooling power for this hydrogen liquefier. A dynamic simulation model based on Ecosimpro has been established according to the designed process flow. The pressure ratio of the helium compressor is 2/16 bar. The helium mass flow...
With the rapid development of world economics and increasing environmental problems caused by the harmful gaseous emissions, the low or zero emissions and frequently reused resources, renewable energies are regarded as sustainable replacements to fossil fuels. Hydrogen, as a kind of clean and efficient energy, would play a key role in future energy systems of the world and possible to become...
The commissioning of China Spallation Neutron Source(CSNS) cryogenic system was completed on July, 2017. It run 258 days totally until July, 2018, and the time of the longest continuous running is 184 days. CSNS passed national accept on August, 2018. Now it is running steady from September 19th. There is no any fault in the process of running. However, cryogenic system need to be improved in...
A thermodynamic study is carried out for the design of hydrogen liquefaction systems with pre-cooling to utilize the cold energy of Liquefied Natural Gas (LNG). As liquid nitrogen is commonly used as pre-cooler of hydrogen liquefaction, LNG is proposed as an alternative, since the need of liquid hydrogen and the import of LNG are simultaneously increasing in Korea. Two different liquefaction...
Bi-2212 is a round-wire, high temperature superconductor that develops high Jc for high-field magnets when it is overpressure (OP) processed. Recent advances in Bi-2212 powder, wire fabrication, and OP heat treatment have improved the performance of the Bi-2212 wire. We are designing, winding, OP heat treating, and characterizing the performance of Bi-2212 coils and comparing their measured...
Superconducting vortex physics has been a topic of interest since the discovery of the oxide high temperature superconductors (HTS). Two driving forces are behind this interest, on the one hand the attractive new physics and on the other the pursuit of technological uses. The complex vortex phenomena in oxide HTS arise from the strong influence of thermal fluctuations, which is a consequence...
Significant increases in the current-carrying capacity (Ic) of Ag-sheathed Bi-2212 over the past several years has made this material a viable candidate for high-field magnets. However, the management of Ic degradation as a function of applied strain remains a challenge, as does the implementation of overpressure processing (OP) heat-treatment conditions for magnets. In this study, we...
Bi2Sr2CaCu2Ox (Bi-2212) is the only high temperature superconductor (HTS) available in the round wire form preferred by magnet builders. Recent advances in the processing have raised its critical current density (Jc) > 6500 A/mm2 at 4.2 K and 15 T, placing Bi-2212 at the forefront of candidates for future HTS high field magnets. The key microstructure for high Jc is a unique a-axis grown...
REBCO wires with artificial pinning centers (APCs) are known to have extremely high Jc at low temperatures and high magnetic fields. Although understanding of the behavior of Jc when tilting the applied magnetic field from the wire surface is still insufficient, information on the angular dependent Jc is very important in coil design. In current REBCO wires, nanorods are often used for APCs...
Achieving high Jc in Bi2Sr2CaCu2Ox (Bi-2212) round wire requires overpressure heat treatment (OPHT) to eliminate current-limiting bubbles. The OPHT has a maximum temperature of ~890 °C and is done with 50 bar overpressure with 1 bar oxygen partial pressure (PO2). During OPHT, the diameter of the Bi-2212 wire shrinks about 4%, with about 80% of this densification occurring during a 2 h hold at...
Nb3Sn superconducting wires are used for TF coils of ITER. Since fusion neutrons will stream out of a plasma vacuum vessel and reach TF coils, the conductors will be irradiated by the neutrons. The bronze-root Nb3Sn wire and the internal-Sn Nb3Sn wire were neutron irradiated at a fission reactor in Belgium and the critical current of the irradiated samples were evaluated with 15.5 T...
It is well known from designs analysis and data, that much lighter weight, higher power density and more efficient motors and generators will be enabled by HTS provided it is developed in suitable forms, preferably operating at or above 40 K. Although DC rotors can be wound with HTS tapes, for example 2G, to generate the required 3 to 5 T fields, stators operate in AC mode albeit at lower...
Engineered nanoscale defects within REBa2Cu3O7-δ (REBCO) based coated conductors are of great interest for enhancing vortex-pinning, especially in high-applied magnetic fields. We have conducted extensive research to optimize vortex-pinning and enhance Jc via controlled introduction of various types of nanoscale defects ranging from simple rare-earth oxides and Ba-based perovskites to double...
In superconducting magnet system of fusion machines, glass fiber reinforced composite insulation material is the main candidate which is used for insulation material of superconducting magnet coils, Electrical insulation breaks, structural and support material for electrical isolation. Even after blanket shielding, the irradiation effect of neutron, degrades the properties of insulation...
The European Spallation Source ERIC (ESS) is going to provide long-pulsed cold and thermal neutron fluxes at very high brightness. They are produced by a linear proton accelerator with an average beam power of 5 MW, which is directed onto a tungsten target at a pulsed repetition rate of 14 Hz.
Two cryogenic hydrogen moderators, to which subcooled liquid hydrogen is supplied at 17 K and 11...
The present paper illustrates a case study in the progress of ongoing research work to develope a 100 litre Helium cryostat with in-situ recondensing facility.The cryostat with a cryocooler sock comprises of 46 components assembled in an optimal sequence. Cryostat development involved thermal load estimation, mechanical design, fabrication of components and sub-assemblies. The cryostat deploys...
Vuilleumier (VM) type pulse tube cooler is a novel kind of cryocooler to obtain liquid helium temperature which had been experimentally verified. However, the efficiency is not satisfying. Based on previous work on a low pressure ratio system, a numerical investigation that explore the effect of high pressure ratios on refrigeration performance is presented in this paper. The research system...
Superconducting machines are attractive for several industries; electric power utilities and industrial applications prefer higher efficiency and ease of operation; aerospace applications like compact lightweight and attractive efficiency; and wind-farm applications want high-efficiency, compact and lightweight generators.
Conventional machines are constrained to operate within saturation...
Coated conductors have high potentials for the wide application field especially in a magnetic field at high temperature. Recently, an electric propulsion system for aircraft using superconducting technologies has been considered to aim a high power density. In our design of the system, the superconducting generators and motors are connected by the superconducting cables. In this system, the...
Since 2014 a conceptual design study is ongoing at CERN for defining Detector Magnets for the Future Circular Collider. A new 100 km circular collider is foreseen whereby collision products are probed by new particle detectors. Magnet variants were optimized for the case of electron-positron (ee), electron-hadron (eh) and hadron-hadron collisions (hh) detectors. This year 2019 the conceptual...
The Future Circular Collider study (FCC) includes the design of detector magnets for the FCC-ee (electron-positron), covering the energy range 90 to 400 GeV and requiring a 2 T solenoid for particle spectrometry, and for the FCC-hh (proton-proton) with 100 TeV collision energy and a 4 T detector solenoid. For both solenoids and their cryostats, CERN is developing an innovative and challenging...
Superconducting power devices offer a high ampacity and power dense solution for power systems of terrestrial electrical power grid, electric aircrafts and electric ships. High Temperature Superconducting (HTS) technology allows to conveniently vary the power loadings by varying the operating temperatures. The deeply coupled electrical, thermal, and magnetic field relationships of...
Absolut System has built a 30K and a 10 K remote Helium cooling loops used as vibration free cooling source, respectively for IR detectors electro-optical characterization test bench and two-stage optical cryostat.
The circulation loops are based on a by-passed flowrate from either a two-stage Gifford–MacMahon cryocooler or a two-stage Pulse Tube cryocooler. Dedicated compact and high...
We present the measured thermal resistance of copper-to-copper interfaces with several intermediate contact-enhancing materials as a function of temperature and pressure. Devices such as superconducting coils are increasingly being operated conduction-cooled, with a cryo-cooler acting as a drain for heat loads. The interface with the cooler typically involves at least one clamped connection to...
Because of low rotational speed, conventional ship propulsion motors are characteristically large, heavy and have poor efficiency. For direct drive propulsors, the drive motor is in line with the propulsor located at bottom of the ship hull. The V-shape hull usually has limited space for drive motors. Because of this, multiple motors are employed in line to drive a propulsor. Compared to...
Raising critical current density Jc in high temperature superconductors (HTS), such as YBa2Cu3O7, is an important strategy towards commercial applications. Development of strong nanoscale artificial pinning centers (APCs) in APC/YBa2Cu3O7 nanocomposites represents one of the most exciting progress in recent HTS material research. Significantly raised in-field Jc has been demonstrated in...
The Polish Free Electron Laser facility (PolFEL) is currently under development at the National Center for Nuclear Research in Swierk, Poland, by consortium of eight Polish scientific institutions and two industrial partners. In the first stage, this fully superconducting linear electron accelerator will consist of an electron gun and four RI-HZDR type cryomodules, each housing two ...
This paper will present the methodology developed by Absolut System for the design and optimization of high capacity cryopumps required for the testing and qualification of electrical propulsion thrusters.
Design, production and tests of a complete test chamber will be presented, including the LN2 feed thermal shrouds and the cold traps thermally anchored to a single stage AL230 type...
G. Churu1, J. A. Demko1 , A. Mole1, R. C. Duckworth2, H. Lu3, S. Malakooti3, N. Leventis4
1LeTourneau University, 2100 South Mobberly Avenue, Longview, TX 75607 USA
2Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN, 3783, USA
3The University of Texas at Dallas, Richardson, TX, 75080, USA
4Missouri University of Science and Tecnology, Rolla, MO 65409, USA
The use and...
Cryogenic Energy Storage (CES) system has large power generation capability, and comparable cost with respect to the non-cryogenic technologies (pumped-hydro, compressed air energy storage systems) while not being location specific unlike the non-cryogenic energy storage systems. It also is environment friendly. High-energy requirement for liquefaction process in the CES system, however, leads...
In the last 20 years, 2-stage cryocoolers have been found to provide an optimum solution for a wide range of applications like low temperature physics, superconducting cold electronics, cryopumping and superconducting magnets. For a proper design of helium cryostats with significant cold masses connected to the first and second stages of cryocoolers, it is important to have a load map (also...
Although the low temperature thermal expansion properties of quite a few materials have been reported in the literature, the need for the confirmation of the relatively sparse data and the generation of new data for different and new materials is needed. Here we report thermal expansion measurement data on an array of materials ranging from neat resins to high strength super-alloys as well as...
Fully turbo-electric propulsion systems for e-aircrafts need fully superconducting generators and motors with lightweight, compactness and high efficiency. High stability and reliability are also required for safety. That forces us to utilize HTS tapes which can operate in liquid nitrogen. The most important issue to realize them is the AC loss reduction of the armature windings. In our...
Artificial pinning centers (APCs) of varying types and nano-scale size have been successfully introduced into (Y,RE)Ba2Cu3O7-x ((Y,RE)BCO or Y-RE-Ba-Cu-O) thin film superconductors by different processing methods, in order to strongly pin the quantized vortices. As a result, the critical current densities (Jcs) of these high-temperature-superconductor (HTS) films have been dramatically...
AFCryo is a joint venture company between Fabrum Solutions, of New Zealand, and Absolut System, of France specialising in the development and delivery of cryogenic equipment utilising patented membrane cryocooler technology.
A commercial product range has been developed over the last 5 years using an innovative concept of a metallic membrane Pressure Wave Generator (PWG) patented by Callaghan...
The Macroflash instrument is a flat plate boiloff calorimeter that provides effective thermal conductivity (ke) data for a wide range of materials from thermal insulation to structural composites to ceramics. This device has become an indispensable tool for NASA researchers in recent years. The apparatus and method provide a practical, standardized approach to measure heat transmission through...
The Institute of Plasma Physics, Chinese Academy of Sciences (CASIPP) has completed the manufacturing and testing of the helium cryogenic subcooled testing platform (CSTP). The CSTP system mainly as a distribution system and testing platform for some key cyrogenic equipment, such as the cold compressor (CC), helium pump, venturi flow meter, etc. This paper describes the CSTP system and...
In order to increase the magnetic field and temperature margin of superconducting magnets, a test facility of a 700W@3K sub-cooled helium was proposed to decrease the operation temperature from the 4.5K saturated helium to the 3K sub-cooled helium. The process flow of 3K sub-cooled helium test facility has been designed with two cold compressors arranged in series to provide 700W@3K sub-cooled...
The subcooled helium cryogenic testing platform with cold compressors has been operated successfully in the end of 2018 at the Institute of Plasma Physics, Chinese Academy of Sciences (CASIPP). It is the first subcooled helium cryogenic system based on the cryogenic decompression technique in China, which has been designed and constructed over two years by our own team. The subcooled helium...
The High-Luminosity LHC project – HL-LHC aiming at peak luminosity above 5.0*10^34 cm-2.s-1 consists in replacing the matching sections on both sides of the ATLAS and CMS experiments. To complement new focusing quadrupoles, this upgrade considers using the so-called superconducting crab cavities, never operated so far with protons and therefore requiring qualification with beam. To this aim, a...
The demand for liquid helium (LHe) for users at CERN without dedicated infrastructure is set to increase due to future projects and experiments in the Antiproton Decelerator. LHe is supplied to the users by means of 500-l dewars filled in by the central liquefier (B165) that comprises a cryogenic plant of 100 W @ 4.5 K. In addition, the Superconducting Cable & Wire Test Facility (B163) located...
A new compact test facility for testing compact superconducting magnets down to 4.2 K using cryogen fluids has been developed at CEA Paris-Saclay. This facility has been constructed to test the solenoid magnets to be produced for the next Soreq particle accelerator (SARAF) project. The magnets are cooled with liquid helium at 4.2 K and the liquid bath can be pressurized up to 2 bars to...
Fermi National Accelerator Laboratory (Fermilab) has multiple cryogenic test facilities, undertaking testing of superconducting magnets, Superconducting Radio Frequency (SRF) cavities, SRF cryomodules and other helium cryogenic components. The test areas within Fermilab include: Meson Cryogenic Test facility (Meson), Industrial Building 1 (IB-1), Heavy Assembly Building/Illinois Accelerator...
Abstract. Cryogenic valve is widely used in cryogenic systems such as Aerospace propulsion systems and various cryostats. At low temperature, the valve is prone to strength decline, material brittleness and other problems, which easily lead to gas leakage and thus bring security risks. Cryogenic valves must be tested for leakage at low temperature in addition to normal temperature. In this...
To improve measuring sensitivity of an IR detector in spacecrafts, it should be cooled down to cryogenic temperature in a limited space and zero gravity environment, connected to a cryocooler. For the heat transfer from the sensor to the cryocooler, a cryogenic loop heat pipe (CLHP) can be used due to its efficient heat transfer performance and reliability without using mechanically moving...
In this research the performances of nitrogen cryogenic heat pipes with different wick structures were compared under the condition of a wide range of heat load and several filling ratios. The heat pipes tested are commercially available ones, which are originally designed for room temperature applications using water as a working fluid. For the present research working fluid, water, was...
The SC100H linear Stirling cryocooler is designed by Kunming Institute of Physics. The characteristics of the magnetic circuit of the moving magnet linear oscillation motor used in SC100H was analyzed by the theoretical and experimental methods. In this study, a theoretical model of the motor was established, and its structure was simplified for easy analysis and calculation. Using the...
With the development of cryogenics, the demand of cryogenic liquid increases constantly. However, there are some difficulties to control and to adjust the extraction of cryogenic liquid especially for liquid helium. Compared with the immersed pump, the ejector has huge advantages in pumping the cryogenic liquid from cryogenic dewar, like stable operation and simple structure. Considering the...
In several scientific application, where cryogenics is used to cool down cavities or superconductive magnets, ionizing radiation can occur. Ionizing radiation accelerates the aging process of organic materials and leads to a degradation of semiconductors.
Nonetheless, cryogenic applications in high physics facilities require a precise and reliable control of the flow, the temperature and the...
Adsorption behavior of helium on activated carbon is expected to be used in the regenerator of 4-K class cryocoolers to improve the performance of the refrigerator. Since the amorphous carbon structure based on graphite slice is closer to the actual activated carbon, we use Grand Canonical Monte Carbo (GCMC) method to simulate the adsorption of helium on the amorphous carbon in low...
A dedicated vertical cryostat has been developed and commissioned at STFC Daresbury Laboratory for qualifying 84 high-beta SRF cavities for the ESS (European Spallation Source). The cryostat is designed to test 3 dressed cavities in horizontal configuration in one cool-down run at 2K. The cavities are cooled with superfluid liquid helium filled into their individual helium jackets. This...
Various functional insertion components (FIC), directly connecting a cold mass and the ambient environment, are irreplaceable and play crucial technical roles in many superconducting cryogenic applications. However, such components also bring a huge heat leak to the cold mass within the cryostat. The heat leak is usually much greater than that through entire evacuated MLI insulation system...
High temperature superconducting (HTS) cable, hallmarked with high energy density and compact corridor occupation, advanced rapidly in the past decades. In practical operation, it is common that the cable is under a not so straight pathway and slope will make the local cryogen behave against our expectation and hazard the cooling condition. In the paper, we build a detailed slope section model...
The High Luminosity LHC (HL-LHC) project aims at upgrading the LHC collider after 2025 to increase its luminosity by about a factor of five. As part of this upgrade, new magnets will require an electrical powering system where the power converters are placed in a newly dug service gallery to shield them from the radiations of the colliding beams. The electrical powering will be ensured via a...
A cryogenic cooling system is designed for three-phase 23 kV-2 kA superconducting fault current limiters (SFCL) under development as an Open R&D Program of KEPCO. The goal of this design is a compact, efficient, and cost-effective cryogenic system as commercial product, based upon our successful long-term operation of distribution level SFCL’s. Three phases of HTS components are immersed in a...
STFC Daresbury Laboratory has an ongoing R&D program for developing superconducting thin film technology for superconducting radio frequency (SRF) acceleration cavities. A number of A15 films has already been deposited at various deposition conditions, with various structure, morphology, and on various substrates. This has created a need to measure a range of superconducting properties of the...
CERN has lately defined the features of the possible next-generation high-energy hadron-hadron collider (FCC-hh): it would be located in a 100 km circumference ring, with a target center-of-mass energy of 100 TeV, achievable through the collision of counter-rotating proton beams with an energy of 50 TeV. Because of their high energy, the proton beams circulating in the accelerator would...
Superconductivity of alkali-metal(A)-doped fullerenes was found in 1991. A-doped fullerides AxC60 [0<x<6] are particularly interesting since their structures and electronic properties are strongly related to the doping carrier concentration. The compound, A3C60, shows superconducting transition at 19K (A=K), 29K (A=Rb) or 33K (A=Cs2Rb). Various types of fullerene-based supramolecular materials...
Thermodynamic properties of superconducting state in the $\rm H_{5}S_{2}$ system were analyzed precisely. The calculations were carried out in two cases: included the lowest-order vertex correction-scheme VCEE (Vertex Corrected Eliashberg Equations), on the other hand we get the model without the vertex corrections, the so-called CEE scheme (Classical Eliashberg Equations). It has been...
Our reserch was focused on ${\rm PbH_4(H_2)_2}$ which is the first of plumbanes homologous serie dopped by a hydrogen. Superconducting state in a homologous series wasn’t checked yet. This is a very interesting issue against of Ashcroft’s thesis about superconductivity in hydrogen rich compounds. This compound connects the heavy element like lead and the lightest – hydrogen. If the properties...
The transition metal oxide interface has attracted extensive attention due to its unique strong correlation properties. In particular, LaAlO3/SrTiO3(LAO/STO) interface [1], has a high mobility of two-dimensional electron gas (2DEG), and specific physical phenomena such as superconductivity [2,3], ferromagnetism [4], and the coexistence of superconductivity and ferromagnetism [5,6] have been...
The addition of different insulating, non-reactive nano-phases to YBa2Cu3O7-δ superconductor thin films improves current density by combining different flux pinning mechanisms. Barium Hafnate (BHO) 1D APCs can be tuned by the addition of secondary yttrium oxide (Y2O3) 3D APCs, leading to a different pinning landscape. Thin films are grown via pulsed laser deposition (PLD) by the adsorption of...
The APC/YBCO interface has been reported to affect the pinning efficiency of BaZrO3 (BZO) 1D APCs. Here we provide qualitative and quantitative study of the effect of semi-coherent (BZO) interface on the angular range of pinning by 1D BZO APCs in BZO/YBCO nanocomposite films. A good understanding of the nature of the interface, and its effect on the angular range of effective pinning, is...
Superconducting Nb3Sn films can be synthesized by controlling atomic concentration of Sn. Multilayer sequential sputtering of Nb and Sn thin films followed by high temperature annealing is considered as a method to fabricate Nb3Sn films where Sn composition of deposited films can be controlled by controlling the thickness of alternating Nb and Sn layers. We report on the structural,...
The magnet-scientific method has been adopted for fabricate grain oriented materials in these 20 years using superconducting magnets with large room temperature bore. High magnetic field up to 10 T enabled us to control grain orientation of paramagnetic materials if they have magnetization anisotropy. In the case of cuprate superconductors, the magnetization easy axis is determined by...
Conventionally the fabrication of superconducting thin films is carried out by tedious processes and requires expensive equipment. Here we report the growth of YBa2Cu3O7-x (YBCO) thin films on SrTiO3 substrates by the low-cost chemical solution deposition technique [1]. The preparation includes the precipitation of yttrium, barium and copper acetates in oxalic acid; and directly dripping onto...
Maximizing critical current density (Jc) and minimizing flux creep in high temperature superconductors (HTS) is critical for their inclusion in accelerator magnets where both high magnitude and high stability magnetic fields are required. In YBa2Cu3O7-x (YBCO) thin films, critical current density can be enhanced by either the addition of many shallow pinning centers or the addition of fewer,...
Different methods of flux pinning are being tested world-wide to enhance critical currents (Ics) of high temperature superconductor YBa2Cu3O7-x (YBCO) coated conductors exposed to high magnetic fields. Magnetic materials are interesting to consider as flux pinning additions because of their potential for very strong pinning strength. To our knowledge, there have been limited demonstrations...
We analyze the measured critical current reduction in Nb3Sn Rutherford cables under magnet-relevant transverse pressure levels in terms of the filament strain inside their strands. A mechanical 2D model of cables’ cross-section is developed to translate the stress that is applied to the surface of the impregnated cables into a strain distribution on the surface of its strands. The resulting...
Introducing materials with high specific heat (C) to Nb3Sn composite wires is a promising technique to suppress the intrinsic instability in high-Jc wires and also improve their stability with respect to external perturbations, which might help to reduce the long training of Nb3Sn magnets. Experiments on prototype wires have demonstrated its capability to improve conductor stability in...
In general, practical metallic superconducting wires, such as NbTi, Nb3Sn and V3Ga, have a fine multifilamentary configuration. Its predominant reason would be pointed as the reduction of electromagnetic losses, the improvement of intrinsic and thermal stabilities, and the reduction of mechanical strain. In particular on the A15 compounds, the promotion of the chemical reaction through the...
Tube type Nb3Sn wires are high performance conductors that typically reach a Jc of 2000-2500 A/mm2 at 12 T and 4.2 K (1000-1250 A/mm2 at 15 T). The wires have performance similar to that of PIT conductors, but are simpler, cheaper, and can be drawn down to finer filament sizes. The conductor consists of a number of subelements, each consisting of a...
A clear indicator of purity of niobium (Nb) used for fabricating Superconducting Radio Frequency (SRF) cavities is the Residual Resistivity Ratio (RRR) of the bulk Nb. Usual methods of determining the RRR is by Four-probe resistance measurement techniques. This process is destructive in nature and provides an average value of the RRR of the sample that is being used. It has already been shown...
High Purity large grain niobium ingots produced by CBMM, the global leading producer of niobium, have shown advantages in manufacturing superconducting radio frequency (SRF) cavities for particle accelerators in regard to less expensive fabrication and treatment procedures with comparable or better performance. For this application, the homogeneity of the ingot needs to be ensured. In this...
The HTS current leads for the ITER project will be the largest ever operated, with unprecedented currents, up to 68 kA and voltages, up to 14 kV. According to the ITER agreement these leads will be provided in-kind by the PR of China. After an extensive development program at the Hefei Institute of Plasma Physics (ASIPP) and with the support of the ITER HTS working group, the ITER current...
$RE-Ba_2Cu_3O_{7−δ}$ (REBCO, RE = rare earth) coated conductors maintain high current densities in the presence of large magnetic fields, making REBCO a promising conductor for use in high magnetic field applications. Unfortunately, the manufacturing process produces defects, resulting in significant drops in the critical current, $I_c$, along the length of the conductor. Additional variations...
Second generation high temperature superconducting (HTS) tapes have been widely employed in design and development of Superconducting Fault Current Limiters (SFCL) and Superconducting Magnetic Energy Storage (SMES) systems. These systems are generally operated near the critical currents of the coated conductors to get the maximum outcomes thus there will be situations when the hot spots may...
Dielectric insulation systems pose a design and material selection challenges for high temperature superconducting (HTS) power cables. Cryogenic operating conditions cause mechanical stresses and the resulting cracks and voids degrade the performance of electrical insulation systems. Superconducting power cable designs that do not use solid insulation are attractive for low and medium voltage...
We reported previously the ac loss measurements of a CORC wire, which consisted of six 2 mm-wide coated conductors wound into three layers around a copper core. The critical current at the self field and 77 K of each coated conductor was 68 A. In order to compare with these experimental results, we carried out numerical electromagnetic field analyses. Our numerical model was formulated with...
The thermal and electrical contact resistance of 10 stacks of YBCO coated conductor tapes was measured at 77 K. The ten stacks were conduction cooled, and had no insulation or other preparation between the layers. The stack of ReBCO comprised of ten pieces of superconducting tape each 30 cm long. To generate pressure on the stack of ReBCO tapes massive steel plates were used. The force of a...
Current-sharing was measured for fully-excited Nb3Sn Rutherford cable at 4.2 K and various I/Ic, using a superconducting transformer. Interstrand contact resistance was modified by different preparation conditions: as-is and low temperature vacuum diffusion bonding. Measurements were performed in pool boiling liquid helium in background fields of up to 15 T with magnetic fields applied...
Interconductor contact resistance (ICR) is a key property in determining the stability and current sharing of coated conductor cables. Most coated conductor cables have relatively high contact resistance and low current sharing as fabricated because of surface asperities and the oxide layer that forms on the Cu-stabilizer. Here we work to quantify the induced differences in using three methods...
HTS tapes, because of their widths and large shape aspect ratios, have not been readily manufacturable into Rutherford or Roebel cables, even though these kinds of cables are required for many large coil applications. A type of transposed Roebel cable is under development with 2G tape, but its design flexibility is limited, its processing is very complex, and it requires that much of the 2G...
Reinforced round Bi2212-based, high temperature superconducting wires and transposed cables are being developed for use in coils that are problematic with wide HTS tapes, and that need to operate beyond the limits of low temperature superconductors. This paper describes advances in the development of our strong round HTS 2212 wire, scale up to production lengths and fabrication into transposed...
Finite Element Method (FEM) modeling of stability and current sharing in Nb3Sn Rutherford cables was performed. Different values of contact resistances Ra and Rc were selected based on previous values extracted from loss measurements, as well as a set of design values. Current sharing was then projected for these cases. FEM models which mimic the QXF1055z-D cable (here named Q6 cable) and the...
High-temperature superconductor composites, such as coated conductor-based CORC and Bi2212-based cables, are being considered for high field magnets to be used in particle accelerators. Strand magnetization can degrade the magnetic field quality by introducing error fields, and flux creep may lead to drift in the magnetic field value during magnetic field ramp holding sequences, such as at...
Recent developments at Thales Cryogenics have been aimed at improving the performances of 100 W and 200 W input power class flexure bearing Stirling coolers.
The aim of these developments has been threefold: To enable multi-year operation with a vanishingly small failure probability (high availability), to increase the available heat lift at 77 K (high power for zero boil-off), and to extend...
The High Luminosity LHC (HL-LHC) will collect 10 times more particles than the original Large Hydron Collider(LHC). This imposes a significant challenges for radiation tolerance and the speed of the detectors, especially for the calorimetry sensors. As part of its HL-LHC upgrade program, the CMS collaboration is designing a High Granularity Calorimeter to replace the existing endcap...
We present a computational model for a closed cycle dilution refrigerator (CCDR) for space applications. The motivation of the computational model was the design a
CCDR demonstration model for the X-IFU instrument of the Athena space observatory.
We also have applied the computational model to other astrophysical instruments such as PIXIE and LiteBIRD to predict the available cooling power for...
High-speed fully superconducting (SC) machines for aerospace applications need to achieve high power density while reducing losses. To increase the power density and eliminate core losses, an inside out synchronous machine is proposed with the iron yoke replaced with actively shielded coils. The additional coils are placed radially outward to contain the flux within the machine. Since core...
The TFA-MOD method is a powerful way to fabricate $\it{RE}$Ba$_2$Cu$_3$O$_{7-\delta}$ coated conductors ($\it{RE}$BCO-CCs) with high critical current properties with a low fabrication cost. In this study, we focused on the case of BaHfO$_3$ nanoparticles (BHO-NPs, which have a diameter of < 10 nm) in $\it{RE}$BCO-CCs fabricated by the TFA-MOD method with an ultra-thin-once-coating (UTOC)...
Performance of superconducting radio-frequency (SRF) cavities is determined by the property of the material within the first hundred of micrometers from the surface. A general overview of the state-of-the-art surface treatments for SRF application will be presented, highlighting how each treatment change the surface properties, and how that affects the RF surface resistance. Recent R&D...
The Structural Heat Intercept, Insulation, and Vibration Evaluation Rig (SHIIVER) is designed to demonstrate the performance benefits of installing multilayer insulation (MLI) and structural vapor cooling onto a large hydrogen tank as a part of an upper stage. The intent of the 4 meter sub-scale demonstration is to design the MLI in a manner that its performance can be scaled to a full sized...
A proven design for a zero gravity dilution refrigerator consists of three capillaries soldered in parallel to form a heat exchanger. The mixing chamber is an T-junction at the cold end of the exchanger. Almost pure liquid $^3$He and pure liquid $^4$He flow through the two outside capillaries to the cold end where they mix in the T-junction causing dilution cooling. The cold liquid...
FLIR Systems has recently developed and begun manufacturing a miniature linear Stirling cryocooler, the FL-100, which has been designed to meet the needs of compact systems using High Operating Temperature (HOT) detectors. These include low cost, long life, high efficiency, and a very compact packaging size. A compact and efficient drive electronics board, the Cryogenic Cooler Controller...
The performance of multilayer insulation systems (MLI) are often determined not by the bulk acreage insulation, but rather by the design details that allow the insulation to be attached to the hardware it is insulating. To help understand the impacts of multiple different types of seams on blanket performance, calorimeter testing was performed at Glenn Research Center. Seams investigated...
In recent years, demands for high sensitivity observation in astronomical missions are increasing. In astronomical observation, in order to achieve superior sensitivity and energy resolution, cooling down the detector for extremely low temperature (100mK or less) is necessary to reduce thermal fluctuation noise emitted from the detector itself. The purpose of this research is to improve the...
Superconducting winding are enabling for the development of the highest power density motors and generators for aircraft use. It is presently estimated that motors with normal conducting can reach a future limit of at best 20 kW/kg. On the other hand, superconducting winding are estimated to be able to produce more than double this, at 45 kW/kg. Superconducting windings carry very large...
Raising critical current density Jc in REBa2Cu3Oy (REBCO, RE: Y and rare earth) tapes is very important for applications such as rotation machineries and wind turbines. Many types of nano-sized precipitates and defects have been formed to enhance vortex pinning, resulting in an increase of Jc under magnetic fields. Ion...
Niobium used in Nb3Sn multifilamentary superconductor wire and superconducting radio frequency cavities is initially cast and then receives a series of deformation and annealing steps to bring it to final component dimensions. The intermediate and final annealing steps are applied in order to recrystallize and soften the microstructure for subsequent shaping or additional mechanical...
Cryocoolers can experience near-periodic heaving or side-to-side motion and acceleration in some applications, in particular on moving platforms. In this work, the effect of heaving and side-to-side movement on a Stirling pulse tube cryocooler was experimentally studied. Periodic heaving and swaying motions having various amplitudes and frequencies were imposed on a Stirling pulse tube...
The long-term storage of cryogenic propellants on orbit under thermal and pressure control is a promising enabling technology for future space exploration. The combination of vapor cooled shield (VCS) and multilayer insulation (MLI) is considered as an effective passive thermal control method for such missions. To verify the modeling results on the thermal insulation performance by introducing...
An initial prototype of a mixed gas Joule-Thomson (JT) cryocooler was constructed and installed in a test facility to experimentally validate and refine a computational tool developed to optimize the gas mixture composition for a Joule-Thomson cycle with specific operating parameters. The mixture optimization model determines an optimal three-component mixture based on the analysis of the...
Niobium provides the basis for all superconducting radio frequency cavities in use. However, flux pinning at lattice imperfections significantly contributes to degradation in niobium performance at high radio frequency accelerating fields. Lattice defects, such as dislocations and grain boundaries, pin the field inside the material even after the external magnetic field is removed thereby...
For a good cryocooler, besides high efficiency at working temperature, the cool-down speed is also important for some applications. Because of the difference in structure and operation mechanism, different cryocoolers have different characteristics of cool-down speed. This work introduces a Stirling type pulse tube cryocooler with ambient displacer which works at liquid nitrogen temperature...
The thermal insulation performance of the thermal insulation system is crucial for the design and operation of the cargo containment system (CCS) for LNG carriers. The boil off rate (BOR) of the carrier is the main evaluation criterion. In this paper, the geometrical arrangement of the new thermal insulation system applied to a new independent type B LNG mock up tank were proposed, designed...
Earth observation satellites require cryocoolers to cool down their infrared imagers at very low temperatures. Besides having very good thermodynamic performances, satellite cryocoolers are expected to generate as little vibrations as possible. In order to better understand vibration causes between 0 and 500 Hz, the whole cryocooler needs to be modelled. In the literature, two main modelling...
Electrification of transport is a growing trend. Air transportation presents some unique challenges for electrification and these challenges have driven the demand for faster electric rail transport. The CRRC Fuxing high speed train is one example of technology being developed, and tested, to be able to operate at 600 km/h. There is a demand to both increase speed, and number of passengers,...
Most applications for REBa2Cu3O7-δ-based (REBCO, RE = rare-earth) Coated Conductors (CC) require reliable, cost-effective growth processes, but also a high performance in magnetic fields. The latter is addressed by the creation of flux pinning centres, e.g. in form of non-superconducting secondary phases (nanocomposites) or elemental mixing on the RE position. Chemical solution deposition...
High purity Niobium possesses superconducting properties that make it a particularly suitable material for superconducting radio frequency (SRF) cavities. Most SRF cavities are made from rolled Nb sheet material, by deep drawing dishes, cutting a central hole, and joining the dishes with seam welds. Fabrication of seamless Nb tubes by hydroforming could lead to improved economics for seamless...
High capacity Stirling type pulse tube cryocoolers (SPTCs) have promising prospect in high temperature superconductivity and gas liquefaction applications due to their definite potential of high reliability and high efficiency. However, impedance mismatching between the linear compressor and cold head in the high capacity SPTC becomes one of the main problems causing its inefficiency and...
Nitrogen doping and heat treatment procedures have boosted the performance of SRF cavities by reaching higher quality factors (Q ~5E10) due to the lowering of BCS resistance (RBCS). Simultaneous to the decrease in RBCS, an unpredictable variability in cavity Q’s has been observed in both fine grain and large grain SRF Nb cavities that has been attributed to increases in residual resistance...
For those versed in superconductivity, flux pinning and critical current are the keys to improving performance in practical applications. When considering the practical deployment of bulk superconductors in rotating machines, however, the range of practical challenges to deployment is considerably enlarged. In this contribution we describe progress made in an ongoing collaboration between...
An Advanced Metal Organic Chemical Vapor Deposition (A-MOCVD) process has been developed to fabricate REBCO tapes with critical currents over 6200 A/12 mm (engineering current density (Je) = 5200 A/mm^2) at 4.2 K, 15 T which is 7X the Je of commercial REBCO tapes and 5.4X the Je of best Nb3Sn tapes. Such high performance is due to the excellent growth of 4 – 5 µm REBCO thick films and embedded...
Superconducting radiofrequency (SRF) technology is being used in discovery science programs and basic research and it holds the potential for several applications that have a direct impact on society. The advantage of superconducting cavities over those made of normal-conducting metal is their ability to store large amounts of energy with much lower dissipation. The direction of future SRF...
There is worldwide interest for high-speed motors and generators with characteristics of compactness, lightweight and high efficiency for aerospace applications. Several options are under consideration. However, machines employing High Temperature Superconductor (HTS) look promising for enabling machines with the desired characteristics. The machines employing excitation field windings on the...
High magnetic field studies are essential to understand high temperature superconductors. Because of their immense characteristic fields (>100 T) that cannot be reached using conventional DC magnets, measurements in pulsed fields are essential. The advent of hydrogen-based superconductors with critical temperatures in excess of 260 K heightens the need created by Cu- and Fe-based...
Particle accelerators rely on large values of the thermal conductivity of superconducting Nb for best operation. Manufacturing processes for accelerator cavities can alter the thermal conductivity of Nb by varying its purity, dislocation density, and other material parameters. Optimizing the material parameters for enhanced thermal conductivity may adversely affect other desirable properties,...
Multi-scale modelling was performed to account for the mechanical behavior of Niobium sheets. 3D representative volume elements (3D RVEs) were generated to properly account for the microstructure of the Niobium sheets. The effect of microstructure and constitutive model on the macroscopic behavior of single-crystal and polycrystal Niobium sheets was evaluated based on crystal plasticity finite...
Superconducting synchronous machines mostly employ HTS field excitation windings on the rotor operating at cryogenic temperature. These windings are usually cooled by coolant supplied from a stationary source to the rotor with rotary couplings. Closed loop gaseous helium couplings have been employed on mega-watt size machines operating at both low speed and high speed. However, these...
Conductor manufacturers worldwide are now making ReBCO coated conductors with optimized $J_c$ performance for applications at low temperatures and at ultra-high fields > 25T. There are several approaches to improve the whole conductor $J_e$ of ReBCO conductors: artificial pinning centers (APC), increased ReBCO thickness, and thinner substrates are three such thrusts being actively studied....
Additive manufacturing is a promising technology for the fabrication of 3 D Nb cavities for quantum computing. We have used this method to generating 3D microwave resonators for QIS applications (resonators and memories). The need is for the highest possible Q-factor to improve the coherence time for cavity-qubit systems, to minimize de-coherence. Here we present our initial studies on...
There are considerable efforts world-wide to use Superconducting Radio Frequency (SRF) cavities to accelerate charged particles to high energies. These cavities are limited by surface defects which lead to cavity breakdown at high accelerating gradients. A novel near-field magnetic microwave microscope that can study these defects was successfully built using a magnetic writer from a...
Fabricating high purity components utilizing additive manufacturing can be difficult due to contamination (oxygen) of the powder feedstock during handling/screening before the process. Contamination could also occur during fabrication due to the processing environment. Special considerations have to be taken when dealing with high purity materials such as niobium or copper. Here we present...
The Facility for Rare Isotope Beams* is being designed and established by Michigan State University as a DOE Office of Science Scientific User Facility supporting the mission of the Office of Nuclear Physics. More than 90% complete, FRIB will provide world-leading research opportunities with rare isotopes in nuclear physics, nuclear chemistry, and the application of rare isotopes for society....
With the development of DC power supply systems, breaking capacity of circuit breakers has been increasingly unable to meet the growing requirements for DC system short-circuit current level. To ensure the safety of the systems, a fault current limiter must be used in series with circuit breakers. The properties of superconducting fault current limiters such as fast reaction rate, simple...
The 1.3GHz LCLS-II Cryomodule (CM) has 8 cavities and each cavity has 9 RF cells and a 50W heater. The1.3GHz LCLS-II CM is 12.2-meter-long and contains a total 241.3 liters (equivalent liquid) of liquid helium, which is filling up by the 4KW@2.0K cryogenic plant at the Fermilab Cryomodule Test Facility (CMTF). A new dynamic synthesis PID control of 2K cryogenic control system is built to...
Helium widely used as cover gas and purge gas in reactor. During the nuclear fission reaction, a large amount of radioactive krypton and xenon will be produced and diffused to helium continuously, which are need to remove respectively. In this study we designed a cryogenic adsorption separation system based GM refrigerator. According to different requirements for adsorption separation, we...
Pressure sensors and laser ranging are often used to test the dynamic characteristics of pistons. The test results obtained by them are usually intuitive and accurate, however, the debugging process is complex. In order to simplify the test process of displacer dynamics in cryogenic coolers, the vibration signal analysis method is used to test the dynamic characteristics of it, and the results...
The vacuum group of NSRRC developed a task-oriented chatbot application based on LINE message platform in 2018. LINE message is a cross-platform communication software that can be easily used on mobile phone, tablets, and PC. This interactive user interface can not only reply the real-time status of sub-systems when the user has a query but also proactively report alert. The TPS cryogenic...
Normally, in order to characterize multilayer insulation installed onto a test tank, the boil-off of the tank is measured and then heat loads from structural and fluid penetrations are calculated from temperature measurements throughout the system. For the Structural Heat Intercept, Insulation, and Vibration Evaluation Rig testing, it was determined that this approach would have significant...
Most of the mechanical property issues in coated conductors are still unknown. Some of the predictive models that’s has been currently developed have a difficulty in defining the parameters that critically influence stress states of the conductor layers. Also the material properties like young’s modulus; thermal expansion has been assumed in those models. As a result, these models can only...
This paper deals with multivariable on-line model predictive control (MPC) for helium Warm Compression Stations (WCS). During WCS operation, control algorithms must ensure that the constraints are respected. These constraints can be imposed by the system itself (valves open from 0 to 100 %, compressor maximum current and pressure, …), or imposed by the users (valves which must remain closed or...
In many fields of engineering, conception and operation teams need to perform simulations in order to design systems fulfilling the user requirements and to operate the systems efficiently. To simulate a cryogenic plant and its distribution to the end-users, a large number of commercial or homemade tools are nowadays available. However, there is a lack of available solutions for quick dynamic...
The induction heater with DC high-temperature superconducting (HTS) magnetization coil is a promising device for aluminum, copper and brass extrusion billets. Compared with an energy efficiency of just some 50% for conventional technology and limitations in processing speed, the energy efficiency of the HTS DC induction heater increase to more than 80%. The HTS DC magnet with its refrigeration...
In 2018 a new cryostat designed to support operation of a helically-wound-coil superconducting undulator (HSCU) was installed at Argonne National Laboratory’s Advanced Photon Source (APS) synchrotron. Magnet temperatures are maintained near 4.2K by natural circulation of liquid helium (LHe) through the magnet potting, and although the HSCU cryostat operates in “zero boil-off” mode by providing...
The international Facility for Antiproton and Ion Research FAIR is currently under construction at GSI, in Darmstadt, Germany. The core component of FAIR, the superconducting SIS100 synchrotron with a will operate with a high repetition rate of up to 1 Hz. The SIS100 ring with a circumference of 1083 m contains 108 main dipole magnets with a maximal field of 1.9 T. The ion-optical lattice of...
This paper presents results on a design, fabrication, and test of rotor cooling system for a 1-kW-class high-temperature superconducting generator (HTSG). This HTSG technically employs an HTS contactless power supply (CPS) to excite HTS field winding. The rotor of HTSG consists of HTS single pancake coils for field pole and HTS strands of CPS’ rotor. They are directly bathed and cooled...
A new terrestrial gravitational wave detector, Superconducting Omni-directional Gravitational Radiation Observatory (SOGRO), has been proposed in 2016 and seen as a competitive candidate of middle-frequency gravitational wave detector. In this detector, there are three pairs of 5 ton low-temperature superconducting test masses, which are separated by 50 meters and magnetically levitated by...
Quench protection is a major issue for HTS magnets that operate at high current densities with high stored magnetic energy. Quenches do not propagate rapidly in HTS coils and these coils heat up quickly because there isn't enough copper in the conductor. In addition, the conductor critical current and the engineering critical temperature will vary depending on the field orientation within...
Multilayer insulation is considered the most potential heat insulation material in cryogen storage. Various heat transfer analyses have been carried out and the results have been compared with the experiments. However, boundary temperatures of the experiments are certain values due to the limitation of the testing apparatus using cryogen. Therefore, for practical engineering design purpose, a...
Thermal radiation properties of materials are essential for the design of cryogenic apparatus. While the experimental data of the emissivity of materials are not sufficient, especially at cryogenic temperature. In this paper, a home built apparatus based on a two-stage Gifford McMahon crycooler for rapid emissivity measurement was present. Emissivity of materials can be measured rapidly from...
Future accelerators like the Future Circular Collider (FCC) under study at CERN, will be considerably larger than the Large Hadron Collider (LHC) presently in operation, with consequent increasing demands for cryogenically efficient cryostat solutions. MLI insulating systems remain the technology of choice for large accelerators due to the compromise they offer between thermal performance and...
Several astrophysics missions are currently planned, with significant European participations. To reach their targeted performances, cooling down to temperature of 50 or 100 mK, depending on the instrument design is required. Multi stage ADR cooling can provide such performances and is well adapted for space. At the early stage of the mission definition various cryogenics design are considered...
Sorption compressors do not have moving parts and are suitable for driving Joule-Thomson cryocoolers. This allows a complete cryogenic cooling system with the absence of moving parts, which is attractive especially for space applications, as well as for other applications. Sorption compressors are thermally driven, meaning, they operate in heating and cooling cycles. The main drawback of...
Sorption pumped 3He refrigerator systems are a well described method of accessing the ~ 300mK temperature range. However, pulse-tube pre-cooled 3He systems typically also include a pumped 4He refrigerator stage to ensure the efficient condensation of the 3He charge, and a set of heat switches to isolate the sorption pumps during regeneration. Here we show that excellent cryogenic performance...
Operating 6,800 feet underground at the SNOLAB facility in Sudbury, Ontario, Canada, the dilution refrigerator-cooled SuperCDMS experiment has been designed for maximum cryogenic up-time and remote operations. A key element in achieving these goals is a pair cold traps in the helium circulation stream of the dilution refrigerator; the first operating near liquid nitrogen temperatures and the...
Pre-cooling of helium with liquid nitrogen is a good alternative for large scale helium refrigerators for initial cool-down from room temperature to about 80 K due to higher exergy efficiency, higher cooling capacity, and lower demand of heat exchanger area. However, during the initial coo-down, two problems have to be faced for improper liquid nitrogen pre-cooling stage arrangement....
Thermodynamic performance analysis and comparison of two types of miniature liquid nitrogen generators are conducted in this paper. Feed nitrogen (or air) is cooled and liquefied by a propane precooled mixed-refrigerant Joule–Thomson (MRJT) refrigeration cycle, or a feed gas expansion process (precooled Kapitza cycle), respectively. Pure nitrogen supplement and mini air separation columns are...
Due to the nature of fluctuation and intermittency, the increasing penetration of wind and solar power will bring a huge impact to the power grid management. Therefore the concept of liquid air energy storage system was proposed. Compared to compressed air energy storage, liquid air energy storage has a larger storage capacity and no geographic constraints owing to the high density of liquid...
In order to overcome the disadvantages of uncertainty, randomness and intermittency brought by wind and solar energy, different energy storage systems were put forwarded. Liquid air energy storage is an important technology in solving the grid connection problem of large-scale renewable energy. However, the production of liquid air needs a cryogenic liquefaction technology below a temperature...
Liquid air energy storage (LAES) represents a promising solution due to its relatively large volumetric energy density and ease of grid load shifting. In the LAES system, efficiency of heat exchange in each subsystem has an intensely crucial impact on overall system performance, including the selection of heat exchange mode and medium, the setting of minimum heat transfer temperature...
Cryogenic air separation is by present the most economical approach to gain high-purity products in a large scale. Structured packing columns (SPC) are widely focused and applied due to their characteristics of high efficiency and energy saving in the cryogenic distillation process. The main aims of the design of SPC are to reduce energy consumption and initial investment, while its optimal...
The JT-60SA cryogenic system will be operated at cryogenic temperature in 2019 in closed loop, without the cryogenic users (superconducting magnets, current leads, thermal shields). It will be another opportunity to verify the efficiency of the control strategies in order to handle plasma operation planned in 2020. This paper updates the heat load profiles to be extracted by the refrigerator...
Large scale helium liquefaction/refrigeration plant plays a vital role in the advanced large equipment such as fusion reactors and accelerators. A new helium liquefaction cycle with double stage compressor is proposed in this paper, which is different from the Collins cycle. The helium gas from the compressor is divided into two parts. The medium-pressure helium gas as one part flows through...
Co-simulation of Cryoplant and Tokamak superconducting magnet system has been performed to investigate operation performance. Cryoplant model, developed by EcosimPro®, consists of three identical refrigerators connected with integrated distribution box, called CTCB, and distribute the cooling to five Auxiliary Cold Boxes (ACB) for magnets and cryopump cooling. Meanwhile, superconducting...
A refrigerator with 250W cooling power at 4.5K is developed in the Technical Institute of Physics and Chemistry, Chinese Academy of Sciences. This refrigerator operates stably and meets the design target after the test and commission. A dewar is uesed to store the liquid helium produced by the refrigerator. A electronic heater and a thermometer are placed in the bottom of the dewar to test the...
The Shanghai Synchrotron Radiation Facility (SSRF) is an intermediate energy light source built at Zhang-Jiang Hi-Tech Park in Shanghai, China. The RF power and voltage required for storing the electron beam are provided by means of three SC cryomodules, each containing one 500 MHz superconducting cavity. A cryogenic plant with cooling capacity of 650 W at 4.5 K (herein called SSRF-I...
Main technical limitations associated with the traditional industrial fluid systems are the following:
- Slow cooling of equipment in order to reach steady-state operation conditions, and associated with it significant loss of the fluids;
- Insufficient thermal and hydraulic stability, due to harmful physical effects (pressure spikes and surge, overpressure, cavitation, reduced density and...
This paper describes the design and initial operational experience from PIP-II Injector Test cryogenic transfer line. Proton Improvement Plan-II (PIP-II) is Fermilab’s plan for providing powerful, high-intensity proton beams to the laboratory’s experiments. The increased beam power will position Fermilab as the leading laboratory in the world for accelerator-based neutrino experiments. The...
Cryogenic system of the superconducting magnet for COMET experiments has been constructed in the J-PARC. There are three kinds of superconducting magnets such as capture solenoid, transport solenoid and detector solenoid. Former two superconducting magnets are cooled down by two phase flow helium which is supplied from helium refrigerator manufactured by Linde (Sulzer) to overcome required...
The LINAC Coherent Light Source II (LCLS-II) located at SLAC National Accelerator Laboratory (SLAC) in Menlo Park, CA, is a U.S. Department of Energy project tasked to design and build a world-class x-ray free-electron laser facility for scientific research. The Linac has superconducting radio frequency cryomodules that are connected to the cryogenic plant by the Cryogenic Distribution System...
The muon-to-electron conversion (Mu2e) experiment at Fermilab will be used to search for the charged lepton flavor-violating conversion of muons to electrons in the field of an atomic nucleus. The Mu2e experiment is currently in the design and construction stage and is expected to begin operations in 2022. The Mu2e experiment uses 4 large superconducting solenoid magnets including a...
The Shanghai high repetition rate XFEL and Extreme light facility (SHINE) cryogenic test facility main consists of 11 test cryostats, a 1 kW@2K cold box, and the distribution system. This paper provides an overview of the distribution system which includes 11 distribution valve boxes, 2 end valve boxes, and several hundred meters cryogenic transfer line. According to requirements of the 11 end...
The new cryogenic system II project is a part of the upgrade of Shanghai Synchrotron Radiation Facility (SSRF), and will construct one 650W/4.2K helium refrigerator including one 60W/2K refrigerator. The new cryogenic system II will provide 2K/4K liquid helium for one 1.5GHz superconducting cavity, also as the backup of the old 650W/4.2K helium cryogenic system I.
This paper focuses on helium...
Advanced Conductor Technologies is developing high-temperature superconducting Conductor on Round Core (CORC®) cables and wires wound from REBCO coated conductors for use in high-field magnets. Magnet applications on which the conductor development is focused on include compact fusion magnets that operate at currents between 50 and 100 kA at fields of 12 – 20 T and accelerator magnets that...
Superconducting electronics (SCE) has experienced a recent surge in popularity due to a growing expectation of their use in future high-performance computing systems. This talk will cover two main topics that are important for integration of SCE systems: (1) superconducting flexible cables and (2) cable-to-cable connectors for superconducting flexible cables. Over the past several years, we...
Cryogenic atomic force microscopy (AFM) allowed us to directly observe segregation morphology of nanometer size hydride phases (Nb1-xHx), which are responsible for Q degradation of superconducting radio frequency (SRF) Nb cavity at high RF field regime. Although niobium hydride has been recognized with cry-optical microscopy, electron diffraction or ion mass spectroscopy, identification of...
ReBCO-CORC is a versatile and unique multi-tape round conductor, developed for application in magnets, bus-bars and links to operate at elevated temperatures like 30 to 50 K, as well as for application in high-field magnets operating at 4.5 K. Experiments on CORC conductors and their application have been performed by many institutes from all around the globe. In combination with technological...
Planar MgB2 Josephson junctions and series arrays were fabricated by focused helium ion beam irradiation. This technique forms a junction barrier with the use of a 30 keV focused helium ion beam, nominal beam diameter of less than 0.5 nm and dose of 0.9 ~ 3 × 10^16 ions/cm^2, to locally damage a 25 nm-thick MgB2 thin film grown by hybrid physical-chemical deposition on SiC (0001). The...
Nitrogen-doped niobium is one of the recent keystone advances in the field of SRF accelerator physics: N-doped cavities reach unprecedentedly high efficiency at usable accelerating gradients, and the more recently developed “nitrogen infusion” reaches similar efficiency with even higher accelerating field. On the horizon is niobium-3 tin (Nb3Sn), a superconducting compound that exceeds the...
Roebel cables from coated conductors were already tested in first real applications, recently in first sub-size demonstrator dipole insert magnets for particle accelerators, an activity from the EU-project EUcard2 coordinated by CERN. The Roebel HTS approach offers unique properties for magnet applications, such as low AC losses from transposed strands, excellent off-plane bending ability and...
There is a strong interest in superconducting transmission lines that operate at microwave frequencies between milli-Kelvin and temperatures near 100 K. We are developing high-quality thin film REBCO superconductor microwave transmission lines on flexible dielectric substrates with thermal conductivity, microwave loss factor and surface resistance that meet application requirements. The high...
Nb3Sn is the front running alternative material to replace niobium in SRF cavities. The most promising path toward deployement appears to be the tin vapor diffusion coating of Nb cavity, which had achieved significant progress in recent years. To elucidate the growth kinetics of Nb3Sn coating during this process, niobium samples were coated for different duration up to 60 hours. Several of...
YBCO coated conductors are being considered for use in high-field magnets for future particle accelerators, as they allow the development of very high field dipoles and quadrupoles. However, the field quality of these magnets, critical for beam steering and control, is well known to be influenced by conductor persistent currents, or magnetization. Some estimates of how coated conductors might...
MgB2 is a promising superconductor to replace Nb for SRF cavities. Clean MgB2 thin films have a low residual resistivity (<0.1 µΩcm) and a high Tc of 40 K, promising a low BCS surface resistance. Its thermodynamic critical field Hc is higher than Nb, potentially leading to a higher maximum accelerating filed. The lower critical field Hc1 of MgB2 is lower than Nb, but it can be enhanced by...
Ultra-cold Neutrons (UCNs) are extremely slow neutrons of which the kinetic energy is below several hundred neV. As a consequence, UCNs are totally reflected at the surface of certain materials and can be confined in a material bottle. Using this unique property, UCNs are used for various experiments such as neutron electric dipole moment searches, neutron lifetime measurements, and gravity...
The FRIB cryogenic plant has been successfully commissioned, including compressor system, 4.5 K cold box system, sub-atmospheric (2 K) cold box system, and the distribution system for two of the three Linacs. This plant uses the Ganni-Floating pressure process, allowing the compressor discharge and 4.5 K cold box supply pressure to automatically vary from 6 to 21 bar, without introducing...
High-temperature superconductors (HTS) draw much interest in the shipbuilding and other transport industries as the urge to get high-power density and efficient electric propulsion systems. To achieve optimal performance of HTS field pole magnets in motors and generators, it is crucial to regulating the cooling temperature under 40 K and a simple and reliable cooling system is desired. A...
The second generation (2G) coated conductors are considered for applications at relatively high, 20 – 30 K temperature, which can be achieved with an inexpensive single-stage cryocooler. Electromagnetic AC losses in 2G coils account a significant fraction of the total loss budget. It is well known that the AC loss is proportional to the superconductor filament width. However, reducing the...
With its unique band structure endowing it with wideband absorption and exceptionally low heat capacity, graphene is an ideal candidate for the study of single photon detection from the near-infrared regime all the way to the microwave regime. Here we present 1) modeled results demonstrating the promise of the graphene-based Josephon junction (GJJ) as a wideband single photon detector, 2)...
Cold neutrons are down-scattered by isopure superfluid 4He (IPHe-II) with around 0.8 K to become ultra-cold neutrons (UCN). The UCN lifetime strongly depends on the temperature of the IPHe-II. During the beam operation, temperature of the IPHe-II gradually increasing from 0.8 K due to the dynamic heat load. The TUCAN collaboration is now developing the new cryogenic system. There are mainly...
At its maximum capacity condition, the 4.5 K refrigerator system for the FRIB accelerator supports a 180 g/s 30 K 1.16 bar cold compressor return flow, a 14 g/s 4.5 K liquefaction load, a 4 kW 4.5 K refrigeration load, and a 20 kW 35-55 K shield load. Five additional design conditions, ranging from liquefaction to refrigeration and a stand-by/reduced load state, were specified for the sizing...
Superconducting ratio-frequency (SRF) cavities, cooled by superfluid helium-4 (He II), are key components in modern particle accelerators. Quenches in SRF cavities caused by Joule heating from local surface defects can severely limit the maximum achievable accelerating field. Existing methods for quench spot detection include temperature mapping and second-sound triangulation. These methods...
The Michigan State University Facility for Rare Isotope Beams (MSU-FRIB) accelerator utilizes six types of cryo-modules that are being installed in three Linac segments in the FRIB tunnel. The cryo-modules contain both superconducting RF cavities and solenoid magnets with 2 K and 4.5 K refrigeration loads (respectively), magnet lead flow loads and 35-55 K shield loads and power coupler...
A key problem with current cryogenic aircraft propulsion systems is the mass burden of cooling the high power electric motors and electronics. The anticipated significant mass addition required for thermal management can nullify the entire benefit of utilizing electric propulsion in aircraft due to the additional induced drag on the aircraft.
Instead, a thermo acoustic-based cooling system is...
In this work, segment of various HTS cables were measured for loss at high dB/dt in a rotating magnet AC loss machine. The cables types including CORC, Roebel, and TWST cables. The cable were measured in a spinning magnet calorimeter (SMC). This test device has a spinning rotor which consists of permanent magnets arranged in a Halbach array, with the sample exposed to an AC field of 0.566 T...
Fluxonium is a multi-level superconducting artificial atom. Its rich spectrum and selection rules provide promising solutions to standing problems in quantum computing such as low coherence and spectral crowding. In this talk, we describe our progress towards constructing a quantum processor based on fluxonium qubits. More specifically, our current focus is to experimentally realize a...
In a narrow channel, boiling heat transfer in He II is much different from that in the case of an open bath. Even under saturated pressure condition, rapid temperature rise due to the onset of film boiling is not seen when the bath temperature reaches the lambda temperature, but only temperature oscillation is detected. The behavior of this state looks like the nucleate boiling, though it is...
The FRIB cryogenic engineering group designed and built the sub-atmospheric cold box which supports the 2 K (31 mbar) operation of the FRIB accelerator cryo-modules. The centrifugal cryogenic (cold) compressors, designed with room temperature motors and active magnetic bearings, were supplied by Air Liquide to FRIB specifications and were integrated into the cold box which was built on site....
Continuous and efficient sub-Kelvin cooling for uninterrupted operation of cutting edge detectors, both in space and on the ground, is critical for top performance in many NASA missions. The development of a sub-Kelvin Active Magnetic Regenerative Refrigerator (AMRR) will provide distributed and continuous sub-K cooling to space instrumentation via circulation of a 3He-4He mixture. This system...
The cryogenic system for the Facility for Rare Isotope Beams (FRIB) produces refrigeration required to support 2K, 4K and 35-60K shield loads for the linear accelerator consisting of forty six cryomodules, four superconducting dipoles and fourteen superconducting magnets for the experimental system. The controls system for cryogenics was designed, installed, and commissioned with the goal of...
A new experimental set up for measuring the breakdown strength of gas media in non-uniform electric field at cryogenic temperatures and high pressures is described. Measure of breakdown strength of helium gas at 77 K and 293 K in a non-uniform electric field with a field efficiency factor 62.5% are presented. The results suggest that the breakdown strength in non-uniform electric field relate...
A no-insulation approach is now of great interest for use in magnets and coils made with YBCO coated conductor. The low inter-strand electrical resistance allows current sharing between layers of the coil, and the associated high thermal conductivity allows for thermal sharing. However, it is of interest to know what actual level of layer to layer electrical and thermal conductivity is needed...
Nonequilibrium quasiparticle excitations (QPs) are known to be a significant source of dissipation in superconducting quantum devices, though their observed density at 20 mK remains a mystery. In this talk, I will discuss our recent work utilizing offset-charge-sensitive transmons to probe QP dynamics. We detect QP tunneling events by coherent mapping of charge parity onto the qubit state and...
The design for the FRIB helium compressor system, used for the cryogenic refrigeration, was mainly based on the advancements developed for NASA James Webb project, improving the efficiency, reliability and maintainability from previous helium compression systems. The skid designs were further improved, first for the JLab 12 GeV project, and now with additional improvements for the FRIB...
A typical Adiabatic Demagnetization Refrigerator (ADR) has modest cooling power, on the order of a few microwatts. Thus, understanding heat loads going into and generated within the ADR is vital to its efficiency as well as the efficiency of the total cryogenic system of a spacecraft. One of the many sources of heat that effects the total cryogenic system is the parasitic heat due to AC loss...
The U.S. Air Force Research Laboratory (AFRL) facility for the measurement of alternating-current (AC) loss in superconductors at high B*dB/dt has been recently tested and calibrated for operation. The test device has a spinning rotor consisting of permanent magnets arranged in a Halbach array; which exposes samples in a stator position with a peak radial field of 0.57 T, and with high...
The recent commissioning of the 36 T Series-Connected Hybrid Magnet at the National High Magnetic Field Laboratory has uncovered an undesirable consequence of using super critical helium for cooling of superconductors. This new “dry-magnet” cooling technology greatly reduces the LHe requirements of the magnet and may be utilized more frequently in the future. Because the supercritical helium...
In spray cooling liquid drops impact the hot wall and depending on the wall temperature the drop either touches-down (contact boiling) or levitates (film boiling). The latter case results in a great reduction in heat transfer by the insulating vapour layer under the drop. Here, we study this phenomena for cryogenic systems, where we investigate the impact of a liquid nitrogen droplet on a...
Developments over the past few years allow Linde Kryotechnik to economically replace the turbines of a cryogenic plant with state of the art technology leading to several advantages. Stand out among others are higher efficiency of the turbines, easier operation of the plant, increase of reliability and an update of the design point regarding current customer demands which improve the overall...
In the framework of 'Flightpath 2015' the European Union set ambitious goals for the aviation sector. Compared to a typical new aircraft of the year 2000 the goals for reduction of CO2 and NOx greenhouse gas emissions were set to 75% and 90% per passenger kilometer, respectively. Aircraft movements during taxiing should be emission-free and the anticipated noise reduction of a flying aircraft...
Hyper Tech Research will report on progress towards developing magnesium diboride superconductor wires, coils and magnets for commercialization efforts, with a specific emphasis on conduction cooled MRI and AC motor/generator applications.
While the energy relaxation times (T1) of superconducting qubits have improved greatly since the birth of the field, much work remains to better understand the limitations on lifetimes and how best to extend them. It is widely observed that qubits exhibit time-dependent fluctuations of their T1 times, but the main sources of this process remain a mystery. Among the leading candidates are...
A fundamental challenge with High Temperature Superconductors (HTS) is their high critical temperature (Tc) values and the stability that they impart when used in a magnet device with sufficient stored energy. Low normal propagation velocities and high stability of HTS wires cause localized damage due to an excessive peak hot spot temperature during a quench. Protection of HTS magnets for...
Turbo- expander is the heart of the helium refrigerator, and the gas bearing as the critical component influences the stability of the turbine. There is 300K operating temperature difference between the expansion wheel and the gas bearing in the helium turbine. Therefore, it is necessary to consider the thermodynamics of the bearing-rotor when studying bearing dynamic stability. In this paper,...
Critical current density (Jc) of in-situ powder-in-tube(PIT) processed MgB2 has still to be improved for practical applications. One of the problems of in-situ PIT MgB2 wires is the low mass density of MgB2 core. The density of MgB2 core of in-situ PIT wire fabricated by the conventional technique is as low as ~50%. It is considered that the microstructure of Mg/B powder cores including the...
Baby-IAXO is a new helioscope, currently under construction design, which will look for axions or axion-like particles (ALPs) originating in the Sun via the Primakoff effect. The hypothetical particles can transform into photons in the presence of a strong magnetic field, and then be detected. The superconducting magnet for this system is composed of two 10-m long racetrack coils, spaced by...
Pulsating Heat Pipes (PHP) are excellent heat transfer devices, constituting the thermal link between a cold sink and an object to cool. The interest for developing cryogenic pulsating heat pipes to cool superconducting magnets is growing because of their lightness and high thermal performance. A numerical model has been developed using the Navier-Stokes solver from ANSYS Fluent software to...
Cold compressor is the core component to develop the facility of large-capacity refrigeration at superfluid helium temperature. It is operated under extremely low temperature and low pressure which involves technical issues about temperature and heat flux such as failures of the actuating motor resulting from overheating and performance decrease due to heat leak to cryogenic side. To analysis...
Second Generation High Temperature Superconducting (2GHTS) power systems are being developed for a variety of applications including the electrical power grid, industrial applications, data centers, high energy physics, electric ships, and electric aircrafts. There are some common requirements and design features for HTS devices for all the applications. However, the design requirements for...
Advanced-Internal-Magnesium-Infiltration (AIMI) MgB2 strands are typically processed with the temperature higher than Mg melting point (650 oC) and heating times of 1 ~ 4 h; therefore, the formation of dense MgB2 layer in typical AIMI strand results from liquid - solid state reaction between liquid magnesium and nano-sized boron powder. In this study, the microstructures and critical current...
Dissipation engineering has emerged in recently years as a promising way to allow efficient control of complex quantum systems. The key ingredient for such dissipative quantum control is to synthesize non-trivial dissipation operators (jump operators), such as linear superposition of photon loss in two oscillators or (nonlinear) two-photon loss in one oscillator. In this talk we present...
It is a well-known observation that a low conductive coating on a metal decrease the overall cooling time of a metal when quenched in liquid nitrogen. The early transition to nucleate boiling regime from the film regime is discussed in the literature as the main cause of this enhanced cooling rate. However, till now optimization of the coating thickness to minimize the cooling time has only...
High-effectiveness heat exchangers are a ubiquitous component of cryogenic systems, but their performance typically falls short of model-based expectations. The following paper details modeling efforts of a heat exchanger designed to achieve an effectiveness in excess of 99% within a prescribed envelope of volume, weight, pressure drop, and operating conditions. Simulation efforts focus on...
In this work, exploration on upper critical field (BC2), irreversible field (Birr) properties and structural properties on MgB2 wires and bulks has been made via alumina fiber strain engineering approach and rare earth oxide (REO) addition approach. Alumina fiber was used in a series of bulk samples in MgB2 (1-x) Al2O3(x), with x being 0, 1 mol%, 3 mol%, 5 mol% and 8 mol%. Another set of MgB2...
Lightweight and powerful technologies for hybrid-electric propulsion technology on-board transport aircraft are needed. GREEN laboratory with the support of DGA and SAFRAN Tech proposed an innovative electromagnetic design using High Temperature Superconductors (HTS) wire and bulks. This motor concept is very promising and can be upscaled easily to deliver large power to mass ratio...
Slush nitrogen is the cryogenic two-phase fluid with small solid nitrogen particle suspended in liquid nitrogen, which can be potential coolant for high-Tc superconductor thanks to its high density and large heat capacity. The present work focuses on the heat transfer of slush nitrogen. A visual experimental apparatus was built for studying the pool boiling of slush nitrogen. The freeze-thaw...
Reducing liquid hydrogen boiloff from storage tanks is a key challenge facing the nascent hydrogen vehicle economy in addition to extended mission space-stage vehicles. However, the extreme cryogenic environment of liquid hydrogen necessitates novel refrigeration methods with components engineered for high-reliability. This paper presents initial experimental results of a Heisenberg Vortex...
Next generation electric power systems require higher capacity, efficiency, and stability to meet the demands of increasingly complicated grid systems. High-temperature superconducting (HTS) Conductor on Round Core (CORC®) power transmission cables provide unique solutions by offering high operating currents and current densities in a very small cable cross-section, which can also...
To enable turboelectric aircraft that utilize fully superconducting motors and generators, testing of high-current, low-AC-loss superconducting wires and coils must be performed. A preliminary investigation was conducted on the critical current capability of a magnesium diboride sample and on the complications that arise from testing the sample with a cryocooler. While a cryocooler provides...
Superconducting qubit designs with topological protection against local noise hold the promise of significantly increased coherence times and higher gate fidelities than is possible with conventional qubits. We are developing one such protected qubit design — the hybrid charge-parity qubit — that combines arrays of conventional Josephson junctions and high, but not extraordinarily high,...
The consortium of the Advanced Superconducting Motor Experimental Demonstrator (ASuMED) will develop, build and test the first fully superconductive motor for aerospace applications. The cryogenic topology of the motor is based on a dual-cryostat concept, which consists of two separate cryostats for the rotor and stator. The rotor cryostat design is particularly challenging because of the...
Medium-sized cryogenic applications such as local hydrogen liquefaction or HTS power applications require temperatures below 77 K at some kW cooling power. These conditions are efficiently reached by cryogenic mixed refrigerant cycles (CMRC). The CMRC development relies on physical property data of cryogenic fluid mixtures that is not available for most binary and multi-component systems.
The...
A proof-of-concept, two-condenser nitrogen pulsating heat pipe (PHP) has been developed for use in applications with redundant cryocooler installations. The PHP design presented here comprises two independent PHP condensers, each thermally sunk to an independent cryocooler cold head, with the two associated PHP evaporators attached to a common heat load. With two installed cryocoolers this PHP...
In this paper the feasibility of producing Fe(Se,Te) Coated Conductors on simple metallic templates is studied. Two routes were tested: i) Rolling-Assisted Biaxially Textured Substrate (RABiTS) and ii) unbuffered Invar 36 substrates. For route i), we started from commercially available Ni – 5 at.% W tapes which show an out-of-plane orientation of about 6° and an in-plane orientation of 5.3°; a...
With the advent of high-power pulse tube refrigerators cryogen free research tools providing mK temperatures and moderate applied magnetic fields have become commonplace. For large scale applications, complex and ultra-high field superconducting magnets liquid helium reservoirs remain a well-considered design option. Truly zero loss, re-condensing cryostats for such large-scale applications...
With the rapid development of life science and the increasing demand of clean energy, refrigeration technology in the temperature range from 80 to 230K is widely required. Mixed-refrigerant Joule-Thomson Refrigeration (MJTR) systems have distinct advantages in this temperature range: i.e., simple structure, low cost, convenient cooling power adjustability, and high reliability due to...
Superconducting electronics and spectral-spatial holographic systems are being developed for advanced digital communications. These devices must operate at cryogenic temperatures of near 4 K. Liquid helium is undesirable for mobile missions due to logistics and scarcity, and commercial low-temperature cryocoolers are unable to meet size, weight, power, and environmental requirements for many...
A scalable process has been developed to fabricate low AC loss cable from second generation high temperature superconducting (2G HTS) coated conductors with an emulated Rutherford twisted conductor topology. The process uses an indexed tape design to precisely align separate YBCO tapes to form a single tape structure making it compatible with a reel-to-reel production process and involves a...
Iron pnictide superconductors are very attractive for applications in the high magnetic field region, because of their large upper critical field, small anisotropy, etc. In the past few years, substantial efforts have been made to improve the transport performances of 122-type iron-based superconducting wires and tapes by ex-situ PIT technique. Recently, we have made further improvement in the...
Superconducting qubits are an attractive candidate for building quantum information processors. However, existing control techniques do not scale well to large multi-qubit arrays. A promising candidate for scalable control is the Single Flux Quantum (SFQ) digital logic family. In an initial single-chip implementation, the fidelity of SFQ-based qubit gates was limited by quasiparticle (QP)...
Cryogenic two-phase flow widely exist in the cryogenic fluid transport processes. While accurate measurement of phase distribution and void fraction has always been a difficulty in practical engineering applications. In this study, the boundary capacitance values are used as a non-invasive measurement method to detect the phase distribution and void fraction of cryogenic two-phase flow....
Superconducting joints are one of the crucial components to make iron-based superconducting wires or tapes successful for future high-field application. A process for fabricating superconducting joints between Sr1-xKxFe2As2 (Sr-122) tapes is developed for the first time [1]. The diffusion bonding of the iron-based superconducting joint was achieved by hot-pressing process in Argon atmosphere....
Driven by global growth in demand for high-speed mobility, as well as a need to ensure profitability and sustainability of aviation into the future, it has been recognized that a strategic transition towards alternative propulsion and energy sources is necessary. To facilitate ensured energy availability and dramatic decreases in warming potential of commercial air travel into the future, a...
Superconducting qubits are coherent artificial atoms assembled from electrical circuit elements and microwave optical components. Their lithographic scalability, compatibility with microwave control, and operability at nanosecond time scales all converge to make the superconducting qubit a highly attractive candidate for the constituent logical elements of a quantum information processor. In...
Hydrogen has long been recognized as highly desirable for space transportation. The primary advantage of hydrogen for space applications is that in chemical or thermal propulsion systems, the exhaust products are of low molecular weight and accelerate readily. This results in very high specific impulse (propulsive efficiency). The key challenges with hydrogen applied to space propulsion are...
Future large-scale quantum processors (i.e. 100s of qubits), especially those based on superconducting circuits, will require large cooling powers (~10s of microW) at very low temperatures (<50 mK) with stringent temperature stabilities to avoid quantum decoherence and thus guarantee successful operation of such systems. One attractive option for providing this cooling is through Continuous...
Historically, NASA has performed many large scale hydrogen ground test to measure the performance of technologies such as insulation, pressure control, line and tank chill-down including venting of vapor. More recently, NASA has focused on the development of numerical codes to predict the performance of these systems and the fluid and thermodynamics within the tanks themselves. Development of...
Quantum information processing in the microwave domain will require large numbers of high quality, well-controlled qubits. Construction of such a system as a monolithic block presents a host of design, engineering and characterization challenges. An appealing approach is to build complexity with many smaller, independently testable modules, connected together in a network. A promising way to...
In Japan, aiming for low emissions of aircrafts, the national project for the development of electric propulsion systems began last June. First fully turbo-electric propulsion systems for e-aircrafts have been conceptually designed. Output power was set to 20 MW for aircrafts with around 150 passengers, such as B737. The propulsion system is composed of fully superconducting generators,...
Superconducting quantum processors are controlled and measured in the analog domain and the design of the associated classical-to-quantum interface is critical in optimizing the overall performance of the quantum computer. Control of the processor is achieved using a combination of carefully shaped microwave pulses and high-precision time varying flux biases. Measurement of quantum states is...
The aerospace industry is the last transportation industry to implement hybrid-electric technology for propulsion. Nearly exponential growth is occurring recently for electric aircraft propulsion, with reportedly with more than 300 startup companies worldwide formed in the last 2-3 years, and supported by Airbus, Boeing, Embraer, Rolls Royce, Uber, Google, Intel, and others. A 6-9 passenger...
The cryogenics group at NASA’s Goddard Space Flight Center has a long-standing development and test program for laboratory and space-flight adiabatic demagnetization refrigerators (ADRs). These devices are used to cool components to temperatures as low as 0.05 K. At such low temperatures the ADR systems can provide a few micro-Watts of cooling power, so it is important to minimize the...
CERN operates and maintains several large cryogenic systems including those serving the LHC complex and its associated detectors, together with cryogenic Test Facilities and distribution services. Outsourcing of Operation and Maintenance to an industrial partner was implemented in 2016. It allows the cryogenics group to activate different level of services starting from basic technical support...
Origins is a Mid IR to Far IR Astrophysics Flagship (multi-$B) Mission that has been studied over the last 2 years by NASA for potential flight in the mid 2030’s. The wavelength range of interest for this mission is 3 to 600 microns, with an objective of having a noise floor of the sky background for this range. This means cooling the telescope to nearly 4 K. The telescope size/collecting...
This presentation discusses recent research and technology development at the NASA Glenn Research Center on superconducting electric machines. Specifically, the presentation will discuss the design, development, operation, and test capabilities of a superconducting coil testbed to measure alternating current (AC) losses for both low- and high-Tc superconductors. AC losses are important in the...
The trend to all digital processing and software defined radio receivers was driven by a lack of flexibility, reliability and loss in the analog processing block of receivers. While the flexibility of software defined radio is clear, cryogenic temperatures offer an opportunity to exploit lower thermal noise in standard components and increase overall system efficiency and performance by...
The cryogenics and fluids branch at NASA’s Goddard Space Flight Center is currently developing a high-efficiency, vibration-free, flight-worthy Continuous Adiabatic Demagnetization Refrigerator (CADR) that consist of two modular units: one that lifts ~6 microW at 50 mK while rejecting its heat to a 4 K thermal sink, and another unit that provides a constant 4 K cooling stage while rejecting...
In the framework of a world-wide international collaboration, the FCC-hh, a 100 TeV hadron collider in a 100-km long tunnel, is proposed as a future circular collider beyond LHC at CERN offering the broadest discovery potential at the energy frontier.
For such high performance hadron collider, the cryogenic system has to distribute very large cooling capacities all along the 100-km tunnel for...
The RESOLVE instrument on the upcoming XRISM mission is a rebuild of the SXS instrument that successfully demonstrated high resolution X-ray spectroscopy on the Hitomi mission using a microcalorimeter array at 50 mK. As with SXS, the RESOLVE instrument requires High Temperature Superconductor (HTS) lead assemblies to carry high current to the Adiabatic Demagnetization Refrigerator (ADR) while...
A solution for a “vibration-free” Joule-Thomson cooler using a sorption compressor is presented to answer the needs of potential future Earth Observation IR missions with low micro-vibration levels requirements from the European Space Agency.
The adopted solution includes a closed cycle J-T cooler, using nitrogen as working fluid with an expected cooling power of $1.5$ W @ $80$ K. The fluid...
The Large Hadron Collider (LHC) operates using superfluid helium provided by eight large refrigeration units (2.4 kW @ 1.8 K each). These units supplied by specialized cryogenic industrial suppliers are composed of serial hydrodynamic cold compressors based on an axial-centrifugal impeller coupled with volumetric warm screw compressors.
The process control systems delivered by the suppliers...
J. Cha, B. Carroll, J. Rodriguez, K. Maynard, M. Romero
The ECOSystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) instrument, launched on June 28, 2018, has completed six months of operation in space. ECOSTRESS is a multispectral thermal infrared imaging spectrometer and its primary mission is to investigate and understand how climate change affects water and carbon...
Superconducting power systems, a promising technology for electric aircraft and all-electric ships, are expected to have many power conversion stages among generators, transmission cables, storage devices, and loads. However, the current technology does not allow power conversion stages to be operated at cryogenic conditions. The lack of such technology deteriorates the overall system...
It is well established that superconducting materials will emit microwave/terahertz radiation when illuminated with a femtosecond infrared laser pulse. Typically this phenomena is examined by illuminating a voltage biased superconducting thin film bridge. In this investigation an inductively charged superconducting thin film ring is considered. We believe the configuration lends itself to a...
We describe the design and testing of the Cryogenic Flex Cable (CFC) delivered for the Near-Infrared Spectro-Photometer (NISP) instrument for the ESA Euclid mission. The Euclid spacecraft is scheduled for launch in the summer of 2022. It will observe ~1/3 of the total sky using a telescope with 1.2m SiC primary mirror, passively cooled to ~125K, and containing Visible Imager (VIS) and NISP...
The accelerator cryoplant (ACCP) providing the cooling for the cryomodules and the cryogenic distribution system for the cold part of the ESS proton linac is being built and commissioned at the European Spallation Source (ESS) in Lund, Sweden. The ACCP warm compressor system (WCS) consists of several compression stages. The sub-atmospheric pressure stage (SP) is used to compress helium coming...
Absolut System is building a 40K vibration-free cooler for ESA earth observation program. This application required small cooling power in the 40K temperature range but extremely low exported vibration level, high efficiency and mass competitive technology.
In addition, a scale-up of the product is on-going to offer a lightweight solution for superconducting motors for hybrid-electric...
A high Technology Readiness Level cryocooler with significant cooling in the 2K to 4K regime will enable a variety of missions ranging from large infrared space telescopes to superconducting and quantum applications. The cryocooler for the MIRI instrument on JWST was designed for operation at 6K, and with relatively minor changes this design can achieve significant lift in the 2K to 4K region....
RAON is a heavy-ion accelerator under construction by IBS (Institute for Basic Science) in Daejon in South-Korea. The aim of the project is to explore the origins of chemical elements, to study new isotopes and to perform research on applied medical and new materials using rare isotopes. For the second linear accelerator (LINAC), a cryogenic plant of 4 kW @ 2.05K will be necessary to maintain...
Current proposed NASA missions to Moon and Mars involve producing cryogenic propellant in-situ to reduce launch mass and requirements. One technique for liquefaction of the gases produced through electrochemical processes is to circulate cold gaseous neon or helium through broad area cooling tubes attached to the outside of the propellant tanks. To determine the performance of this...
Inductors typically consist of copper or aluminum windings around magnetic cores. However, as magnetic cores are not suitable for cryogenic applications due to substantial eddy current loss generated by reduced core resistivity at cryogenic conditions, coreless inductor designs are preferred for cryogenic applications.
In this paper, we report the electrical performance including ampacity...
As superconductor digital integrated circuits (ICs) mature to productization, they require rapid evaluation of multiple copies to obtain statistical operational data. These data are used for assessing model-to-hardware correlation and facilitate iterative IC design development. The Integrated Cryogenic Electronics Testbed (ICE-T) is a cryogen-free test platform, which can test multiple chips...
The ITER Cryodistribution (CD) system distributes cryogenic cold power equivalent to 75 kW at 4.5 K and 1300 kW at 80 K, from the cryoplant to the applications, namely superconducting magnets, cryopumps etc. The Cryoplant Termination Cold Box (CTCB), which is the largest CD cold box, interconnects 3 liquid helium (LHe) plants, two 80 K helium plants, 1 LHe tank at one end, and 5 auxiliary cold...
The implementation of polymer films as cryogenic propellant bladders could mitigate sloshing in a microgravity environment. However, prior research into cryogenic bladders was discontinued in the 1970s due to reportedly high permeabilities of hydrogen and helium through polymer films at cryogenic temperatures. These permeabilities differed from the Arrhenius relation by increasing as...
High temperature superconducting (HTS) devices enable high current densities to be achieved. For some applications the required operating temperature is less than 50 K and gaseous helium (GHe) is utilized as the cryogen instead of the commonly used liquid nitrogen. These applications include devices with MgB2 as the superconductor, and for HTS motors, generators and, magnets which operate with...
The development of Turbo-Brayton technology started in 2007 with the goal to provide efficient and reliable solution for the cooling of HTS cable. Since then, several units have been manufactured, tested and operated for many different applications, as the temperature range covered by the technology is very wide, ranging from 20K to 200K. In August 2018, the first operation of a Turbo-Brayton...
Earth’s Moon harbors valuable water ice deposits within the permanently shadowed regions (PSR) of craters and possibly other geological features. Of primary value in the water are the molecular hydrogen and oxygen constituents useful as spacecraft propellants, fuels to generate power, and life support to enable mankind’s further exploration of the solar system and beyond. Acquiring the water...
Electrical energy storage devices are critical components of electric power systems of every aerospace vehicle. They are needed for many functions, such as an energy source for electric-vehicle (EV) propulsion, as an electrical accumulator unit (EAU) to handle 2-3x higher-than-average transient loads both on/off the power buses, for emergency power during system failure, and to provide...
