Conveners
C3PoB - Pulsed Heat Pipes and Heat Transfer
- Wolfgang Stautner (GE Global Research)
- Amir Jahromi (NASA / GSFC)
Compared with conventional heat pipe, pulsating heat pipe (PHP) takes advantage of several outstanding features, such as great heat transport ability, strong adjustability, small size and simple construction. In our previous work, a 4-turn helium PHP was developed and the effective thermal conductivity was determined to be 4800-13000 W/m∙K, which was dramatically higher than that of copper...
This paper explores the development of a 3D model using ANSYS Fluent to characterize the two-phase (gas/liquid) flow of helium in a cryogenic pulsating heat pipe. The model includes condensation and evaporation phenomenon and uses the Vof model to capture aspects of the two phase flow. Temperature dependent properties were applied for helium in the range between 2.2 K and 5.2 K. Bubble...
The High Luminosity LHC (HL-LHC) is a project aiming to upgrade the LHC collider after 2020-2025 in order to increase the integrated luminosity by about one order of magnitude and extend the operation capabilities until 2035. An upgrade of the focusing triplets insertion system for the Atlas and CMS experiments is foreseen using superconducting magnets operating in a pressurised superfluid...
Pulsating Heat Pipes (PHP) are passive two-phase heat transfer devices consisting of a long capillary tube bent into many U-turns connecting the cooling part to the heating part. They are thermally driven by an oscillatory flow of liquid slugs and vapor plugs coming from phase changes and pressure differences along the tube. The coupling of hydrodynamic and thermodynamic effects allows high...
In this paper, a detailed experimental study was carried out to investigate the two phase flow patterns of R600a in a smooth horizontal tube with an inner diameter of 6 mm. The experiments were performed at conditions covering saturation pressures from 0.215 to 0.415 MPa, mass fluxes from 67 to 194 kg m-2 s-1 and heat fluxes from 10.6 to 75.0 kW m-2. Based on high speed camera four main flow...
The experiment PVLAS1) aims at the measurement of the vacuum polarization as predicted by the QED (Quantum Electro Dynamics).In the new experimental set-up2) at INFN Ferrara two mirrors, 3.5 meter apart, constitute an optical cavity (with finesse=700 000) for a 1.064 micron Laser. Between the two mirrors two independent high field permanent dipole magnets (Halbach type) are installed, which...
In this paper, oscillating flow in heater and cooler of β-type Free-Piston Stirling Engine (FPSE) have been investigated in order to highlight the impact of alternating heat transfer on its performance. This analysis is based on the Finite Speed Thermodynamics and Isothermal methods, considering different heat and power losses in Stirling Engine, meanwhile physical modeling are carried out by...
The detectors of the Super Cryogenic Dark Matter Search (SuperCDMS) experiment at SNOLAB will operate in a six-layered cryostat with thermal stages between room temperature and the base temperature of 15 mK. The inner three layers of the cryostat, which are to be nominally maintained at 1 K, 250 mK, and 15 mK, will be cooled by a dilution refrigerator via conduction through long copper stems....
Cryosorption pump is a capture vacuum pump which retains gas molecules by chemical or physical interaction on their internal surfaces when cooled to cryogenic temperatures. Cryosorption pumps are only the solution in nuclear fusion systems to achieve high vacuum in the environment of hydrogen and helium. An important aspect of this development is the proper adhesion of the activated carbons on...
