在两相粘性跨音速喷管流动中簿层方程的一种隐式求解方法*

本文略去沿流动方向的粘性,将任意曲线坐标系中无量纲化的N-S方程简化为薄层方程.采用隐式近似因子分解法求解气相控制方程,采用特征线法跟踪颗粒,然后获得两相跨音速湍流充分耦合的数值方法.其中,颗粒尺寸是分级的,用参考平面中的拟特征线法处理喷管的粘性亚音速进口边界条件,湍流采用代数模型.该计算方法应用于火箭喷管两相粘流计算,并预估了固体火箭发动机的推力和比冲,计算与试验结果吻合很好.文中还讨论了不同颗粒尺寸、不同颗粒质量百分数和颗粒尺寸分级等对流场的影响,分析了颗粒、二维径向分速和粘性对发动机比冲的影响.本文的方法具有节省机时的优点,尤其是对颗粒尺寸分级的计算,效果更为显着.

An lmplicit Algorithm of Thin Layer Equations In Vlscous Transonic,Two-Phase Nozzle Flow

Omitting viscosity along flow direction,we have simplified the dimensionless N-Sequations in arbitrary curved coordinate system as the thin layer equations.Using theimplicit approximate-factorization algorithm to solve the gasphase governing equ-ations and the characteristic method to follow the tracks of particles,we then obtainedthe full coupled numerical method of two-phase.transonic,turbulent flow.Here,particle size may be grouped,the subsonic boundary condition at entry of nozzle is ireatedby quasi-characteristic method in reference plane and the algebraic model is used forturbulent flow.These methods are applied in viscous two-phase flow.calculation of rocket nozzle and in the prediciton of thrust and specific impulse for solid propellant rocket motor.The calculation results are in good agreement with the measurerment values.Moreover,the influences of different particle radius,different particle mass fraction and particle size grouped on flow field have been discussed,and the influences of particle two-dimensional radial velosity component and viscosity on specific impulse ofrocket motor have been analysed.The method of this paper possesses the advantage of saving computer time.More important,the effect is more obvious for the calculation of particle size being grouped is more obvious.