Numerical studies on the effects of hot end temperature on a single-stage multi-bypass type pulse tube cryocooler

摘要

The performance of pulse tube cryocooler is affected by the temperature of hot end, which is mainly influenced by the temperature of environment. Effects on a single-stage multi-bypass type pulse tube cryocooler are investigated by means of numerical simulation. For different opening of multi-bypass orifices, the refrigeration performances are studied when hot end temperature changed in a certain range, and some numerical results are provided and analysed. Together with the temperature at cold head and multi-bypass position, the mass flow rate through the multi-bypass orifice is affected significantly by the temperature of hot end, and the optimum opening of multi-bypass orifice decreases with hot end temperature increasing from 240 K to 320 K. Therefore, to select an optimal opening of bypass orifice according to the temperature of operating environment is necessary.