行波和驻波模式下热声振荡的临界温度梯度

THE CRITICAL TEMPERATURE GRADIENT OF THERMOACOUSTIC VIBRATIONS IN STANDING AND TRAVELING WAVE MODES

热声机械作为一种能量转化装置。其效率于传统发动机还有较大差距。本文讨论了热声发动机在驻波和行波两种不同工作状态下，其声功率产生的临界温度梯度与流道尺寸和工作介质的关系，得出了两种模式下最佳的工作条件。结果表明；采用行波形式的热声发动机结构，可以有效降低临界温度梯度，提高热致声的效率，同时可以利用一些低品位来做为热声发动机的高温端。

The paper compared the different working mechanism of thermoacoustic engines under traveling and standing wave modes, and discussed the dependence of critical temperature gradients of acoustic power generation rate on flow dimensions and working medium. The results indicate that, due to effective utilization of heat energy, the traveling mode thermoacoutic engine can self-oscillate under lower critical temperature gradients than the standing mode thermoacoustic engine.