驻波型热声制冷机回热器的结构优化

Optimization on Characteristic Parameters of Stack for the Standing-Wave Thermoacoustic Refrigerator

对驻波型热声制冷机的回热器进行了理论研究,通过对绝热情况下回热器内系统能流的分析,得到了以回热器位置和结构参数为变量并能够较为准确地预测出回热器时均温度差ΔTm的解析表达式.将所得解析表达式与实验结果、线性化结果进行比较,表明了结果的准确性.运用所得结果对板叠式回热器在声场中的位置、板叠厚度和板叠间距进行优化,得到了回热器最优位置xS=f-1(ΔTm),最优板叠间距2y0/δκ=3.3～3.4,最优板叠厚度为2l/δκ=0.7.

For the stack of the standing-wave thermoacoustic refrigerator, the essential features of the time-averaged heat flux density distributions inside a thermally isolated thermoacoustic stack were theoretically studied. The analytical formulation of the accurate mean temperature difference ΔTm was achieved. In comparison with experimental results and linearization results, the derived formula to calculate the mean temperature difference ΔTm was proved to be correct. The position and characteristic parameters of stack for the standing-wave thermoacoustic refrigerator could be optimized with the use of analytical formulae obtained as follows. The optimal position of stack is xS=f-1（ΔTm）, optimal plate distance is 2y0/δκ=3.3～3.4 and the plate thickness is 2l/δκ=0.7.