湍流、喷雾模型对氢氧火箭发动机燃烧仿真的影响

基于完善的压力隐式算子分裂(PISO)算法,通过改变κ-ε两方程湍流模型和喷雾模型,对氢氧火箭发动机不稳定燃烧进行数值仿真。比较理论分析和数值仿真的结果得出,在二维情况下,液滴碰撞模型和TAB液滴破碎模型不适于模拟氢氧火箭发动机不稳定燃烧;TVB液滴破碎模型与κ-ε两方程湍流模型的组合情况能够捕捉到燃烧室中的压力振荡,但不能体现出振荡频率;而采用Realizableκ-ε湍流模型不考虑液滴雾化模型时不但能够捕捉燃烧室内压力振荡情况,还能够很好地得出振荡频率的分布情况。

Effects of turbulent and spray models on combustion process simultion of LOX/GH2 rocket engine

Based on the improved PISO algorithm, the numerical simulation for the combustion instability of a LOX/GH2 rocket engine was conducted by changing the turbulent and spay models of κ-ε equations. The compared results of the theoretical analysis and numerical simulation show that in the two-dimensional situation, both droplet collision model and TAB droplet breakup model are not suitable for the numerical simulation of LOX/GH2 combustion instability; the pressure oscillation in the combustion chamber can be simulated by combining the TVB droplet breakup model with the turbulent models of κ-ε equations, but the oscillation frequency can not be simulated; if the turbulent models of Realizable κ-ε equations are adopted without consideration of the droplet spray models, both the pressure oscillation in the combustion chamber and the distribution of the oscillation frequency can be simulated.