Abstract: Numerical simulation was carried out for the flow separation in overexpanded rocket nozzle using Beam Warming approximate factorization method to solve thin layer N S equations. The results indicate that the separation position was determined by the ratio of total pressure to environment pressure.The area ratio of the nozzle has little influence on separation for the same divergent section.For the longer divergent section,the area ratio in which flow separates is smaller.

Key words: Engine nozzle;Nozzle flow;Flow distribution;Numerical simulation;Approximate solution

摘要： 应用 Beam- Warming近似因式分解方法差分求解薄层 N- S方程 ,对某型发动机在多种工况下的分离流场进行计算。结果表明 ,燃烧室总压与环境压强的比值控制分离点位置 ;对于相同的喷管扩张段型面 ,喷管面积比对分离位置的影响小 ;扩张段较长的喷管分离点面积比较小

关键词: 发动机喷管;喷管气流;流动分布;数值仿真;近似解法