A Novel Three-Stage 4 K Pulse Tube Cryocooler
C. Wang
Cryomech, Inc., Syracuse, NY
Abstract
A three-stage pulse tube cryocooler has been successfully developed at Cryomech, Inc. to provide cooling capacities at temperatures around 45K, 15K and 4K. Unlike a conventional staged pulse tube cryocooler, this three-stage pulse tube cryocooler uses a middle bypass to build the 2nd stage cooling station. This design allows us to use parts from our two-stage pulse tube cryocooler, such as the ambient temperature phase shifters, and heat exchangers. The new design makes the cold head more compact and simplifies manufacturing. The three-stage pulse tube cryo- cooler reaches temperatures of 29.3 K, 8.7 K and 2.38 K on three stages in 74 min. It can provide 37W at 45K, 15 W at 15K and 0.3 W at 3.97K simultaneously with an input power of 11.0 kW.
