基于水平集函数的固体火箭发动机瞬态内流场模拟方法研究

针对固体火箭发动机装药燃面退移下的瞬态内流场模拟方法进行研究,采用水平集方法捕获发动机工作过程中的装药燃面,多孔介质模型约束装药区域的流动特性,建立了一种可以准确模拟发动机内流场瞬态流动的水平集和多孔介质耦合方法(LSPM)。采用该方法对有壁面退移的圆管通道流动问题进行了计算,对短内燃管形装药和复杂翼柱形装药发动机进行了模拟。研究结果表明:LSPM计算结果与动网格方法吻合较好,可以较好地处理有界面退移的加质流动问题;LSPM压力和燃面的计算结果与零维内弹道结果基本一致,可以准确计算装药燃面退移下的发动机瞬态内流场。

Simulation of Transient Internal Flow Field of Solid Rocket Motor Based on Level-set Method

A method considering combustion surface regression is developed to simulate the transient flow field of solid rocket motor.The method combining the level-set method with the porous media model can accurately simulate the transient flow field.In this method,the level-set method is used to capture the fluid-solid interface,and the porous media model is used to constrain the flow characteristics of grain region.The transient flows in the circular tube channel with interface regression and the solid rocket motor with short tube and complex wing-shaped charge are simulated to demonstrate the simulation accuracy of the proposed method.The calculated results agree well with the results obtained from dynamic grid method and zero-dimensional internal trajectory theory.It shows that the method can accurately simulate the transient flow with combustion surface regression.