Dynamic experimental study of a multi-bypass pulse tube refrigerator with two-bypass tubes

Abstract

A dynamic experimental apparatus to measure the instantaneous velocity and pressure in the multi-bypass pulse tube refrigerator (MPTR) was designed and constructed. Some important experimental results of the instantaneous measurements of the velocity and the pressure in the MPTR with two-bypass tubes during actual operation are presented. The effects of the middle-bypass version on the dynamic pressure and mass flow rate at the cold end of the pulse tube are evaluated from experimental measurements. DC-flow phenomena are observed in this MPTR. The reasons of the multi-bypass version improved the performance of pulse tube refrigerator are given.