Advances in a high efficiency commercial pulse tube cooler

[摘要] The pulse tube cryocooler has the advantage of no moving part at the cold end and offers a high reliability. To further extend its use in commercial applications, efforts are still needed to improve efficiency, reliability and cost effectiveness. This paper generalizes several key innovations in our newest cooler. The cooler consists of a moving magnet compressor with dual-opposed pistons, and a co-axial cold finger. Ambient displacers are employed to recover the expansion work to increase cooling efficiency. Inside the cold finger, the conventional flow straightener screens are replaced by a tapered throat between the cold heat exchanger and the pulse tube to strengthen its immunity to the working gas contamination as well as to simplify the manufacturing processes. The cold heat exchanger is made by copper forging process which further reduces the cost. Inside the compressor, a new gas bearing design has brought in assembling simplicity and running reliability. Besides the cooler itself, electronic controller is also important for actual application. A dual channel and dual driving mode control mechanism has been selected, which reduces the vibration to a minimum, meanwhile the cool-down speed becomes faster and run-time efficiency is higher. With these innovations, the cooler TC4189 reached a no-load temperature of 44 K and provided 15 W cooling power at 80K, with an input electric power of 244 W and a cooling water temperature of 23 . The efficiency reached 16.9% of Carnot at 80 K. The whole system has a total mass of 4.3 kg.

[发布机构] Lihan Cryogenics Co. Ltd., Shenzhen, Guangdong; 518055, China^1;Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry of CAS, Zhong Guan Cun Dong Rd.29, Beijing; 100190, China^2

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Commercial applications;Cooling efficiency;Cooling water temperature;Electronic controllers;Manufacturing process;Pulse tube coolers;Pulse tube cryocoolers;Run-time efficiency