Journal Article

Investigation on a thermal-coupled two-stage pulse tube cryocooler with multi-bypass working at 8 K

Quan, Jia, Pan, Mingtao, Zhao, Miguang, Li, Yanen, Liu, Chenglong, Yang, Bin, Tian, Bo, Wang, Nailiang, Xing, Enchun

2026

Overview

The Stirling type pulse tube cryocooler (SPTC) eliminates moving parts at the cold end and is driven by a linear compressor at the hot end, thus offering the advantages of low vibration at both ends, high reliability, and long service life, which makes it attractive for various special fields, such as the space field.In practice, there is an increasing interest in providing cooling power at different temperature levels. This paper presents an experimental investigation of a thermal-coupled two-stage pulse tube cryocooler with multi-bypass structures. The experiments investigated the effects of the second-stage operating frequency, charging pressure, and input power on performance. Building upon this, the study explored the interaction between the first-stage temperature, multi-bypass temperature, and second-stage temperature, alongside experimental testing of cooling performance. The experimental results show that through the thermal coupling pre-cooling and the design of multi-bypass structure, the second-stage cold finger can realize the lowest temperature of 5.2 K and the cryocooler can provide 54 mW cooling capacity at 8 K while providing 50 mW cooling capacity at 35 K with the 1st-stage providing 1.5 W of cooling capacity.

• Publisher: IOP Publishing
• Subject: Cooling / Cryogenic cooling / Pulse tubes / Service life / Thermal coupling