声腔深度和相对开口面积的确定

根据二维声腔模型的声学试验结果和四分之一波管的理论公式，给出了直孔(槽)声腔和四种有进口肋声腔的有效深度计算公式。用该公式对几个推力室进行验算，得到可借鉴的声速比数值范围。依据设置声腔的二十多个推力室的稳定性鉴定试验数据，统计得到声腔相对开口面积的经验公式。

Determination of the Depth and Fractional Open Area for Acoustic Cavity

Based on the testing data of 2D acoustic model and theoretical equations for quarter wave tube, a new method for determining the effective depth of different type of acoustic cavities is presented. The sound velocity ratio for several practical thrust chambers can be obtained by the method. The result shows that this value varies from 0.50 to 0.78. Furthermore, according to the stability testing data of more than twenty types of thrust chambers, a new empirical equation for calculating the fractional open area of acoustic cavity is also given out.