EXPERIMENTAL-ANALYSIS OF THE MULTI-BYPASS PRINCIPLE IN PULSE TUBE REFRIGERATORS

This paper describes the structural characteristics and the mechanical performance of a co-axial pulse tube refrigerator with a multi-bypass . Some experimental results and an experimental analysis of the multi- bypass method are also given. The minimum attainable temperature at th e cold end of a co-axial pulse tube refrigerator with multi-bypass is 33 K at a vacuum of 1 x 10(-4) torr. This shows that the performance o f a pulse lube refrigerator is comparable to that of a Stirling refrig erator. Moreover, pulse tube systems would probably be more extensivel y used than Stirling refrigerators because of their advantages in term s of structural simplicity and mechanical reliability.