热声发动机回热器操作因子的优化研究

研究热声热机中回热器长度和工作温度的优化方法.通过对热声学线性公式的进一步分解,提炼出一个量纲一参数———回热器操作因子.相对水力半径和回热器操作因子建立了工作频率与回热器长度及回热器水力半径之间的定量关系.通过回热器轴向尺寸和径向尺寸的一定比例缩放,使得热声系统在不同频率下实现相同的热声转换效率.以两种典型的热声发动机回热器为例,对操作因子进行优化研究,并由此得到了最佳工作效率下的回热器长度和温度分布.

Optimization of Regenerator Operating Factor of Thermoacoustic Engine

The method to optimize the parameters of length and temperature difference of thermoacoustic regenerator is studied. Based on the linear thermoacoustic theory, a normalized parameter named as the regenerator operating factor is extracted. The regenerator operating factor and relative hydraulic radius set up the quantitative relationship among the working frequency, length and hydraulic radius. The thermoacoustic device under difference frequency could work with same efficiency of thermoacoustic transfer by adjusting the ratio of radius dimension to the axis dimension. Above result is of significance to guide the miniaturization design of the thermoacoustic device. Finally, the regenerator operating factors for two types of typical thermoacoustic devices are optimized and their optimal regenerator parameters of length and temperature difference can be obtained.