Design and Comparative Analysis of Thermoacoustic Refrigerators

In this paper, the design of a loudspeaker driven 10 W cooling power stack-based thermoacoustic refrigerator at 3% drive ratio for a temperature difference of 80 K using helium as working fluid is discussed. The refrigerator is designed using linear thermoacoustic concepts. Using linear thermoacoustic equations, a theoretical minimum cold heat exchanger temperature is estimated at 75% porosity of stack-heat exchanger system. This paper focuses on the comparative analysis of the present design with the similar 10 W thermoacoustic refrigerator designs found in the literature. The theoretical performance comparison of TSDH, TDH and CDH resonators designed at 2% and 3% drive ratio is discussed. The resonator designs are validated using DeltaEC software and the results are discussed. DeltaEC simulation results show that the diameter of the vibrating diaphragm of the loudspeaker equal to the diameter of the stack-heat exchangers system has higher electroacoustic efficiency (74.7%) and better performance compared to the smaller diaphragm (42.6%) used in the past research.