The effect of operating parameters in the Stirling cryocooler

This paper presents design, manufacturing process and test results in the optimum operating condition for the free piston free displacer (FPFD) type Stirling cryocooler designed and manufactured by Korea Institute of Machinery and Materials. FPFD Stirling cryocooler is currently under development for cooling infrared detector. The compressor in the Stirling cryocooler uses opposed linear motors to drive opposed pistons. The performance of FPFD Stirling cryocooler is evaluated as a function of charging pressure and operating frequency. In general, as the charging pressure is increased, optimum-operating frequency of the compressor is increased but resonant frequency of the displacer is almost constant. The prototype has achieved no load temperature of 49 K and cooling power of 0.5 W at 72 K.