环流喷管的轴对称湍流流场计算

TURBULENT FLOWFIELD CALCULATION IN ANNULAR NOZZLES

关键词:  环流喷管~+  喷管气流  纳维尔-斯托克斯方程  网格生成  流场仿真  数值仿真

Key words:  Annular-folw nozzle+  Nozzle flow  Navier-Stokes equation  Grid generation  Flow field simulation  Numerical simulation

摘要:

对火箭发动机环流喷管进行了二维数值仿真,用数值方法求解Navier－Stokes方程,数值格式为显格式时间推进格式,湍流模型选择可靠性较好的两层代数湍流模型。由于所研究的流场边界形状复杂,计算中采用了分区的方法。通过多个算例的对比,确定了使环形喷管推力效率较高的几何形状。画出了环流喷管内部的计算网格图、速度矢量图、等马赫线图、等压线图及喷管上壁面及轴线的压力分布图。

Abstract:

This paper is about numeric imitation of annular-flow nozzles of rocket motors.Navier-Stokes equations are solved by numerical methods. The numerical scheme is MacCormack timeforward-push scheme. Zero-equation which has more relibility is selected to apply to turbulent model.Because of complex boundary condition of flowfields region-dividing is used in the calculation.Through contrasting a lot of calculation examples, geometric parameters of annular-flow nozzles withhigher efficiency are found. The final results of flowfield calculation is steady. The graph of equalMach numbers, the isobar graph, and the graph of pressure distribution along nozzle wall and thecentric line of nozzle are drawed with computer. The drawing of computing grid and the vectorialdrawing of velocity of annular-flow nozzle are obtained.