Conveners
C3Or2B - Thermal-Fluid Transport and Properties for Fluids Boiling Above 50 K
- Ian Richardson (Washington State University)
- Jacob Leachman (Washington State University)
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...
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...
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...
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...
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...
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...
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....
