DESIGN OPTIMIZATION OF THERMOACOUSTIC REFRIGERATORS

Thermoacoustic refrigeration was developed during the past two decades as a new, environmentally safe refrigeration technology. The operatio n of thermoacoustic refrigerators employs acoustic power to pump heat. Nowadays, as commercial applications are sought, it is important to b e able to obtain fast and simple engineering estimates for the design and optimization of prototypes. This paper provides such estimates by implementing the simplified linear model of thermoacoustics - the shor t stack boundary layer approximation - into a systematic design and op timization algorithm. The proposed algorithm serves as an easy-to-foll ow guideline for the design of thermoacoustic refrigerators. Performan ce calculations applying the algorithm developed in this paper, predic t values of 40-50% of Carnot's efficiency for the thermoacoustic core, the heart of a thermoacoustic refrigerator. One reason that these eff iciencies have not yet been achieved in devices built to date, is the poor performance of the heat exchangers in thermoacoustic refrigerator s. This issue and other remaining challenges for future research are a lso addressed in the paper. Solving these problems in the near future, we believe, will bring an environmentally safe refrigeration technolo gy a step closer to commercial use. (C) 1997 Published by Elsevier Sci ence Ltd and IIR.