Experimental analysis of the multi-bypass principle in pulse tube refrigerators

Abstract

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 the cold end of a co-axial pulse tube refrigerator with multi-bypass is 33 K at a vacuum of 1 × 10 −4 torr. This shows that the performance of a pulse tube refrigerator is comparable to that of a Stirling refrigerator. Moreover, pulse tube systems would probably be more extensively used than Stirling refrigerators because of their advantages in terms of structural simplicity and mechanical reliability.