Conveners
Thu-Po-3.4: Thermal Properties
- Maciej Chorowski
Thermo-physical and transport properties of fluids at cryogenic temperature deviate significantly from their room temperature properties. The cryogenic fluid properties like density, specific heat, thermal conductivity, viscosity, etc. show non-linear behavior at supercritical regions. Hydrogen, Helium, and Neon being a quantum fluid do not follow the laws of corresponding states and require...
Astronomic instrumentation requires working at cryogenic temperatures and a high stability. It is crucial to understand the properties of materials and contacts among components within the cryostat to be able to achieve the thermal goals in astronomical applications.
To enhance instrument cold structure designs, there's a growing need to perform accurate Finite Element Method (FEM)...
The emissivity of low-temperature materials exhibits variations with changes in temperature. Currently, measuring low-temperature emissivity often includes the use of cryogenic liquids like liquid nitrogen and liquid helium, which presents challenges such as handling inconvenience and limited adaptability to a broad temperature range. Furthermore, materials like aluminum-coated polyester films...
The transfer of vapor-free liquid cryogen through fluid systems in low-temperature applications demands achieving thermal equilibrium between the channel wall and the flowing liquid. This transient cool-down phase, known as transfer line chill-down, poses challenges due to associated complex two-phase heat and mass transfer phenomenon. Accurate modelling of the same is necessary for optimizing...
Cryogenic fluids such as liquid oxygen, hydrogen and nitrogen are used in rockets and superconducting applications. Boiling heat transfer occurs between the liquid and solid interface during initial cooling from room temperature to cryogenic temperature. Boiling heat transfer performance has a significant impact on the cooling speed. The largest heat flow occurs in nucleate boiling, but has a...
Large-scale cold storage plays a crucial role in future net-zero emission scenarios. It is expected to drive advancements in technologies such as liquid air energy storage (LAES) and liquid nature gas (LNG) cryogenic energy utilization, with promising commercial prospects. To eliminate the use of flammable, explosive, and potentially polluting liquid-phase storage mediums, packed bed cold...
Liquid hydrogen (LH2) is gaining attention as a low-carbon energy vector and fuel in the clean energy sector. This has led to a significant growth in the worldwide production and distribution of LH2 in recent years. Today, the distribution of LH2 from the liquefier facility to the user is almost entirely performed by road trailers. In the future, the LH2 distribution via rail cars, the...
Hydrogen is projected to play an important role in the decarbonization of industries that are not readily electrifiable, such as aviation, shipping, and high-energy process industries [1]. To this end, effective solutions for hydrogen transport and storage are needed at a scale far exceeding current capacity. As the hydrogen value chain expands, a wide range of computational modelling tools...
A water hammer is a pressure surge that occurs when a liquid in motion within a pipe is suddenly stopped, often due to a rapid closing of the valve or shutting down of the pump. This abrupt change in momentum creates a powerful pressure wave that can cause severe damage to pipes, pumps, and other components and also leads to reduce the efficiency of the components. Whenever the amplitude of...
This paper designed a detachable cryostat. The cooling capacity is obtained by GM refrigerator and transferred to the test chamber through the copper cold chain. The test chamber is filled with low temperature helium, and the sample is installed in the test chamber. Finally, the temperature of the sample is controlled by adjusting the temperature of the helium atmosphere. The cryostat above...
It was found in our past microgravity experiments that the bubble size was much smaller than the prediction in the vicinity of the lambda point, and the bubbles had unstable interfaces. However, no experimental reports like this anomalous feature of He II boiling at the vicinity of lambda point were shown. Therefore, in this study, we focused on the boiling experiments around wire heater in...
The Main Linac of the International Linear Collider (ILC) includes superconducting quadrupole (SCQ) packages that are located between the superconducting RF cavities, with one SCQ within each of the Type-B cryomodules. This combined-functioned, splittable superconducting magnet focus and steer the electrons and positrons. The magnet is required to be cryogen free, and conductively cooled down...
One of the important aspects of any cryogenic design is to achieve good thermal performance by minimizing the temperature gradient at different contact regions of the thermal mass. In some cases, electrical isolation may be required at contact regions. Different combinations of the thermally conductive and at the same time electrically insulated joints have been characterized using a GM...
Fluid transients resulting from rapid flow acceleration or deceleration can pose a significant risk to the structural strength of fluid handling networks, such as those in cryogenic rocket propulsion systems, LNG transport systems, powerplant flow systems, household water systems and many others. Additionally, due to its oscillating behaviour, fluid transients can lead to the formation and...
The data of the linear thermal expansion (α) and specific heat (Cp) are combined for the study the thermal and magnetic properties of PrBa2Cu3O6+x (PrBCO6+x or PrBCO) ceramic samples in two different oxygenation states: an underdoped (UN) with x = 0.44 and an optimally doped (OP) with x = 0.95. The temperature dependences of the ratio (α/Cp) as well as the effective Grüneisen parameter (Γeff),...
To study the performance of the intermittent flow cold storage surface heat exchanger in the experimental system, the volume selection of the helical tube and its heat transfer characteristics play a crucial role in ensuring the continuous and stable operation of the entire experimental setup. A method for calculating the volume of the helical tube based on the gas vessel dynamics model is...
