Low Temperature Cryocooler

Technology Applications, Inc. is proposing to develop and demonstrate the feasibility of a low-temperature cryocooler (LTCC) that is reliable, has high efficiency and low vibration, is lightweight and compact, and has variable load capability. This system uses a Stirling or pulse tube cryocooler operating at 70 K as a precooler and an expansion-engine-based cold stage. Operating temperatures below 6 K can easily be achieved with Carnot efficiencies greater than 5%. The extraordinary high efficiency is due to the incorporation of a unique expansion engine design that is enabled through application of micro-electro-mechanical systems (MEMS) technology. The development of the MEMS expander assembly and its integrated electronics will revolutionize low-temperature cooling. It greatly increases Carnot efficiency, reducing input power, lowering cost, and providing consistency of performance. Using MEMS fabrication techniques, the LTCC can be made in large quantities with low production costs resulting from the economy-of-scale seen in the integrated circuit industry. Development of this technology will provide an extraordinarily high payoff for future NASA Space and Earth Science Enterprises. The Phase I study will demonstrate feasibility of the LTCC through detailed analyses and identification of the MEMS fabrication processes. During Phase II, a prototype LTCC will be fabricated and tested.