Thermal Analysis and Simulation of Cryopump Based on CFD Method

Abstract

Abstract Based on CFD method, thermal design and numerical simulation of cryopump first array and second array was performed during the cool-down period and the steady state. The analysis of the temperature distribution of the cryopump was made under various conditions, such as operating conditions, the setting of the thermal rods and the thickness of the radiation shield. The const thermal property and variable thermal property was used in this paper to calculate the cool-down process of the cryopump, the effect of the first array structure was also taken into account. Some important results with typical parameters are: The temperature difference of the first array of the cryopump is greatly affected by the working conditions, especially when facing the room temperature vacuum system, the main heat load is concentrated on the baffle; A variable thickness bottom plate can be used to reduce the overall temperature change of the cryopump; The setting of the thermal rods is very useful to reduce the temperature change of the cryopump; The setting of the thermal rods is preferably close to the center of the baffle; If the variable property was not considered, the deviation of the cool-down time is about 24%.