超声速气流中雾化燃料喷射的三维数值研究

首次用双流体模型对雾化燃料在扩张形超燃室中沿九喷嘴顺流喷射的混合问题进行了数值研究。气相用迎风 TVD格式求解三维全 Navier- Stokes方程 ,液相用预估、校正 NND格式求解三维 Euler方程。相间相互作用的常微分方程用预估、校正Runge- Kutta法求解。用三维 Poisson方程生成网格。结果表明 :气相较液相的扩散效果好 ,小直径液滴的扩散效果好。相间速度滑移、改变气相喷射压力和喷射速度对液相扩散的贡献不大 ,但调整喷射角度会明显地增强液相的扩散、混合 ,本文结果未出现阻塞。

Three Dimensional Numerical Simulation of Atomized Fuels Injected into a Supersonic Flow

Numerical simulations were done to study the atomized fuels injected into a supersonic flow in a divergent combustor through nine injectors. Two fluid model was used to describe the two phase flow. TVD scheme and NND scheme were used to solve 3D gas and liquid phase equations, respectively. The gas liquid interaction equations were solved by a Runge Kutta approach. The computational grids were generated by three dimensional Poisson equations. The results indicate that the mixing of droplets with small sizes is satisfactory. But there is a free droplet region near the divergent walls. At injectors, the velocity slip, the gas jet pressure and fuel jet velocity contribute little effects to droplets mixing. By adjusting the jet angle, the mixing of droplets can be enhanced and the free droplet region can be reduced. The shock waves appear at the windward surface between the fuel jet and the inflow.