Design, construction and testing of the prototype cryogenic circulation centrifugal pump for the high energy photon source

A cryogenic circulation pump (CCP) with the small flow rate and low heat leakage, which is the key equipment of the cooling system for the cryogenic permanent magnet undulator (CPMU) and synchrotron monochromator in High Energy Photon Source(HEPS), is developed according to the design parameters and operation experiences. The mechanic structure of the CCP including a motor at room temperature, an impeller and a volute in the cryogenic environment is designed, and numerical simulation on the rotating shaft and internal flows are performed to predict the mechanical and hydrodynamic performances of the pump. Meanwhile, the experimental investigation of the CCP is carried out in the liquid nitrogen (LN₂) cryogenic system, and the hydrodynamic performances of the CCP are verified experimentally. The results are shown that the calculated performances of the CCP are in reasonable agreement with the experimental results, which indicates that the numerical calculation model of the CCP is more effective. Moreover, the deviations of pressure drop and efficiency between the calculation and measurement are analyzed in this paper.