Thermodynamic improvements for the space thermoacoustic refrigerator (STAR)

The objective of the STAR project is to test and space qualify a new continuous cycle cryogenic refrigeration system for cooling of sensors and electronics which is based upon the newly discovered thermoacoustic heat pumping effect. The new refrigerator has no sliding seals, a cycle frequency of about 300 Hz, and uses acoustic resonance to enhance the overall power density and efficiency. This thesis is concerned specifically with the design and testing of the thermodynamic element (or stack), which is responsible for the thermo- acoustic power conversion, and the testing of binary inert gas mixtures as working fluids. Using the refrigerator's coefficient of performance relative to the ideal Carnot coefficient of performance as a measure of efficiency, we have achieved a 93% improvement over previous designs. Keywords: Thermoacoustic refrigerator, Theses.