固体火箭发动机药柱裂纹腔内三维流场瞬态特性分析

以固体发动机药柱内存在的楔形裂纹为研究对象,采用三维流场控制方程,应用有限体积法计算了发动机点火启动阶段裂纹腔内的对流燃烧过程。在裂纹腔侧壁被点燃前,裂纹腔内的燃气压力基本呈均匀分布,且约等于燃烧室燃气压力;在裂纹腔侧壁被点燃后,燃气压力逐渐呈现出上部低、下部高的分布,且腔内平均压力远高于燃烧室内燃气压力;裂纹腔侧壁开口边缘处的推进剂首先达到点火温度开始燃烧,燃面迅速向内推进,燃气以非常高的速度向外流出裂纹腔。

Analysis on 3D transient flow field of crack cavity in solid rocket motor grain

Taking wedge crack in the solid rocket motor(SRM) grain as research object,the convection burning process in crack cavity at the ignition start-up stage was calculated by using 3D governing equations of fluid dynamics and finite volume method.Before ignition of the propellant on the crack cavity side wall,gas pressure in crack cavity presents basically uniform distribution and nearly equals to that in the chamber;after ignition of the propellant,gas pressure becomes low in the upper part of cavity and high in the lower part of cavity,and the average gas pressure in the cavity is much higher than that in the chamber.The propellant on the edge of the cavity operture firstly reaches the ignition temperature and begins burning,then burning surface rapidly spreads toward cavity,finally the gas flows out of the crack cavity at very high speed.