水雾对火箭点火超压抑制效果的参数化研究

为研究水雾对火箭点火超压的抑制效果，采用平面波跨介质传播理论分析水雾对点火超压的抑制机理，得到了影响水雾抑制点火超压效果的主要因子。进而，数值研究各因子对抑制效果的影响规律，分析了在满足火箭安全发射条件下各因子的取值范围。最后，利用均匀试验设计方法设计数值计算的参数水平，采用回归分析方法得到了抑制效果与影响因子之间的参数化模型，并进行了抑制效果的优化研究。结果表明影响点火超压抑制效果的主要因子有:水滴直径、水雾体积分数和水雾层厚度。受水滴直径影响，水雾对点火超压有2种不同的抑制机理。此外，当影响因子在一定阈值内变化时，点火超压抑制效果与影响因子之间存在参数化模型，且置信概率不小于95%。 

Parameteric investigation on ignition overpressure mitigation performance of rocket by water mist

To research the mitigation performance of rocket ignition overpressure by water mist layer, the theory of plane wave propagation in different medium was applied to expore the mechanism for ignition overpressure mitigation by water mist layer. And, main influential factors of ignition overpressure mitigation performance were obtained from theory analysis. Furthermore, the influence rules of the factors on the mitigation performance were studied by numerical computation and the proper value ranges of influential factor under the conditions of rocket safety launching were given. At last, the parameter levels of influential factors for numerical computation cases were arranged by the uniform design. Meanwhile, the parametric model of the influential factors to the mitigation performance was built by regression, and the mitigation efficiency was optimized. The numerical results show that the main influential factors include water droplets diameter, water mist volume fraction and water mist layer thickness. And, there are two different mitigation mechanisms between water droplet and ignition pressure pulse which are closely related to droplet diameter. In addition, there is a parametric model of the influential factors to the mitigation performance when the influential factors falls within some value ranges, and fiducially probability of the model is not less than 95%.