固体火箭发动机内流场解析解与数值解

Comparison of analytical and numerical solutions of mean flow fields in solid rocket motors

对具有燃面减退的固体火箭发动机燃烧室头部的内流场进行了研究。以二维轴对称流动的不可压N-S方程为基础,介绍了解析方法,包括运用空间相似与时间相似原理简化N-S方程以及运用摄动法求解高阶微分方程。之后采用FLUENT软件中的动网格技术,对该问题进行了数值模拟。主要研究了在不同的燃面减退速率及注入雷诺数下,燃烧室头部区域的速度场,压力场及剪应力的分布。通过解析结果与数值结果的比较,发现两者基本吻合,增强了解析解的可信程度。

The mean flow fields in fore combustion chamber of solid rocket motors with grain regression were studied.Based on incompressible N-S equation of two-dimensional axisymmetric flow,the analytical method,which includes not only simplified N-S equation by spatial similarity and temporal similarity but also solving the high order equation by perturbation method,was introduced.With the technology of dynamic mesh in FLUENT software,the mean flow fields were numerically simulated by solving N-S equation.The velocity fields,pressure fields and shear stress distributions were mainly studied for different rates of wall regression and injection Reynolds number.The fact that numerical results are well in agreement with the analytical solutions gains confidence in the analytical approximation.