筒口流场及其对发动机水下点火影响的数值模拟

研究了导弹水下发射时筒口流场特性，并就筒口流场对发动机水下点火初期的影响进行了分析。采用Mixture多相流模型和RNG湍流模型以及动网格技术，求解了不同工况下二维轴对称筒口流场及发动机喷流流场。计算结果表明，水深越大，筒口气泡断裂越早；燃气发生器熄火时，弹底离筒口越远，气泡断裂对发动机影响越小；燃气发生器延迟熄火，有利于发动机喷流的建立。

Numerical Investigation to Outlet Flow Field and Its Impact on Underwater Ignition of Rocket Engine

The feature of outlet flow field underwater and its impact on underwater ignition of rocket engineare researched. The Mixture multiphase model, RNG turbulence model and dynamic girding are adopted to solve axisymmetric outlet lfow ifeld and underwater gas jet at different conditions. The result shows that the deeper the depth, the sooner the cavities break; the farther away from the outlet, the smaller the cavities break impact on the engine; delay lfameout of the gas generator is conducive to the establishment of the jet stream.