Purpose Copper is a cooling transfer material used in cryogenic superconducting systems.The effective thermal conductivity(ETC)of copper in the 4K region is only about 400 W/(m K).Its heat transfer performance is poor...Purpose Copper is a cooling transfer material used in cryogenic superconducting systems.The effective thermal conductivity(ETC)of copper in the 4K region is only about 400 W/(m K).Its heat transfer performance is poor,there are some shortcomings such as large temperature difference,temperature fluctuation lag,cryogenic system layout limited.The ETC value of helium-based cryogenic oscillating heat pipes(COHP)in the 4K region is much higher than that of copper.However,the choice of heating power interval is very important,and the heating power will affect the oscillation characteristics of COHP.Methods In this study,a helium-based COHP heat transfer performance test platform was built in the 4K region,and the effects of heating power and liquid filling rate on oscillation conditions and ETC were studied.The heating power ranges from 0.1 to 0.5 W,and the liquid filling rate ranges from 20%to 87%.Results and conclusion The heating power interval suitable for oscillation behavior is given quantitatively.The intrinsic correlation between ETC and amplitude is further discussed.The results are of great significance for improving the performance of cryogenic superconducting systems.展开更多
Purpose In recent years,with the further development of superconducting technology,superconducting devices have been applied in particle accelerators and synchrotron radiation light source devices.As a new type of hea...Purpose In recent years,with the further development of superconducting technology,superconducting devices have been applied in particle accelerators and synchrotron radiation light source devices.As a new type of heat transfer structure,helium cryogenic oscillating heat pipe can be used to balance local hot spots in superconductors and improve heat transfer performance.Methods In this paper,a two-dimensional two-turns helium cryogenic oscillating heat pipe model is established.The flow performance of helium cryogenic oscillating heat pipe was analyzed by CFD simulation.Results and conclusion The results show that the development of flow pattern in the helium cryogenic oscillating heat pipe first forms bubble flow under the heating of the evaporation section,and then gradually forms slug flow and annular flow.The process consists of initial stage,transition stage and running stage.In the running stage,the effective thermal conductivity of COHP oscillates around 15,000 W/(m·K).展开更多
基金supported in part by National Natural Science Foundation of China(No.11905233).
文摘Purpose Copper is a cooling transfer material used in cryogenic superconducting systems.The effective thermal conductivity(ETC)of copper in the 4K region is only about 400 W/(m K).Its heat transfer performance is poor,there are some shortcomings such as large temperature difference,temperature fluctuation lag,cryogenic system layout limited.The ETC value of helium-based cryogenic oscillating heat pipes(COHP)in the 4K region is much higher than that of copper.However,the choice of heating power interval is very important,and the heating power will affect the oscillation characteristics of COHP.Methods In this study,a helium-based COHP heat transfer performance test platform was built in the 4K region,and the effects of heating power and liquid filling rate on oscillation conditions and ETC were studied.The heating power ranges from 0.1 to 0.5 W,and the liquid filling rate ranges from 20%to 87%.Results and conclusion The heating power interval suitable for oscillation behavior is given quantitatively.The intrinsic correlation between ETC and amplitude is further discussed.The results are of great significance for improving the performance of cryogenic superconducting systems.
基金This work was supported by National Natural Science Foundation of China(No.11905233).
文摘Purpose In recent years,with the further development of superconducting technology,superconducting devices have been applied in particle accelerators and synchrotron radiation light source devices.As a new type of heat transfer structure,helium cryogenic oscillating heat pipe can be used to balance local hot spots in superconductors and improve heat transfer performance.Methods In this paper,a two-dimensional two-turns helium cryogenic oscillating heat pipe model is established.The flow performance of helium cryogenic oscillating heat pipe was analyzed by CFD simulation.Results and conclusion The results show that the development of flow pattern in the helium cryogenic oscillating heat pipe first forms bubble flow under the heating of the evaporation section,and then gradually forms slug flow and annular flow.The process consists of initial stage,transition stage and running stage.In the running stage,the effective thermal conductivity of COHP oscillates around 15,000 W/(m·K).
