火箭冲压发动机反应流场数值模拟

NUMERICAL SIMULATION OF REACTING FLOWS IN DUCTED ROCKET COMBUSTOR

用偶合算法求解三维定常椭圆型Ｎ－Ｓ方程组，计算了火箭冲压发动机内部的湍流反应流场。用有限体积法离散控制方程，用块隐式法求解离散后的代数方程组。湍流流动用ｋ－ε模型描述，湍流燃烧采用掺混控制的局部瞬时不混合模型。实践表明，尽管密度场变化剧烈，仍能快速收敛。算例中网格点数为３９×１３×１８。计算出的燃烧效率符合实验结果。

A solution algorithm based on coupled solution of the fully elliptic three dimensional steady state Navier Stokes equations was developed for the calculation of turbulent reacting flows occured in ducted rockets.The governing partial differential equations were discretized by finite volumes and the nonlinear algebraic equations were solved by a block implicit algorithm.Turbulence was represented by the k ε model and chemical reaction was assumed to occur in one step at an infinite rate,controlled by mixing of fuel and oxidant streams.It is demonstrated that the strategy of coupled solution is rapidly convergent even in the presence of significant density variations.Calculations with grids as large as 39×13×18 have been made successfully in modest computer time.The combustion efficiency calculated is in good agreement with experimental data