An Experimental Study of the Influence of Cold Head Displacement Speed on Single-Stage Gifford-McMahon Cryocooler System Performance

In positive displacement cryocooler systems, the cooling performance is generally driven by the interaction between the compressor’s displacement and the cold head’s displacement. An experimental investigation explored the relationship between performance and cold end displacement speed for a single-stage gas-driven GM-type cold head operated at different frequencies. As loss mechanisms can be frequency related, the investigation also compared varying the cold end displacement by changing stroke length instead of changing operating frequency. Results showing these relationships are presented, and their impact on seal wear and variable-speed operation are discussed.