基于瑞利准则的火箭发动机稳定性缩比方法研究

摘要

The stability-scaling test method based on Rayleigh criterion is presented for the test on combustion stability of high-pressure staged combustion rocket engine. The key parameters that determine the stability are obtained by dimensional analysis and the method determining the scale ratio is given. By criterion, the type of propellant, injection temperature, speed, mixing ratio are the same as full-size combustors; the injector and combustors are geometrically similar to the full size engine. The pressure of the scaled device is higher than the critical one of the propellant. The results indicate that the pressure and the lfow rate of the scaled combustor are reduced greatly.%针对高压补燃循环火箭发动机燃烧稳定性试验提出一种基于瑞利准则的稳定性缩比方法，通过量纲分析得到决定稳定性相似的关键参数，给出缩比尺度的确定方法。通过缩比准则，可使推进剂种类和喷前温度不变、喷注速度不变、混合比不变，喷注器和燃烧室同全尺寸发动机分别几何相似，缩比发动机燃烧室压力大于推进剂超临界值。算例分析结果表明，该方法得到的缩比发动机燃烧室的压力和流量等大幅降低。