Numerical simulation of a GM-type pulse tube cryocooler system: Part I. Characterization of compressors

For the numerical simulation of GM-type pulse tube cryocoolers (GMPTCs), several compressors with different input powers were characterised under static conditions, including their mass flow, input power, discharge and suction pressures. Based on the measured data, the relationships between suction volume flow, exergetic efficiency, and pressure ratio were found to be independent of the working gas amount contained in the compressor package. A method to evaluate the volume distribution inside the compressor package was proposed and verified. The empirically determined relations of suction volume flow and exergetic efficiency together with the volume distributions are given for the measured compressors. With these characteristics, the mass flow, electrical input power, discharge and suction pressures of the compressors operating in a GMPTC system can be predicted at various working conditions.