Investigation on multi-stage centrifugal cold compressors in superfluid helium cryogenic system

Abstract The centrifugal cold compressors are the pressurizing device commonly used in large-capacity superfluid helium systems to connect the 2 K helium tank to the room-temperature screw compressors. In order to provide a large pressure ratio, the cold compressors are connected in the form of multi-stage series, which would result in the stable operating region that is reduced to a certain extent. Therefore, this paper models the multi-stage cold compressors and 2 K superfluid helium system, compares the simulation results with experiment carried out with cold compressor test platform under steady load condition, and analyses the reason for the difference between simulation and experiments.