飞行参数对射流矢量喷管内流场影响的数值模拟

采用三维雷诺平均N-S方程和k-ε湍流模型对固体火箭发动机燃气二次喷射矢量喷管内外流场进行数值模拟,研究飞行参数对矢量喷管内主/次流耦合流场的影响。结果表明,自由来流造成喷管出口附近压力变化,通过喷管内壁面附面层作用影响喷管内部流动特性。飞行马赫数为超声速,或者环境压强较低时,侧向力大小与飞行参数无关。在低空亚声速流中,侧向力随飞行马赫数增加迅速减小,随环境压强降低而减小。

Numerical simulation on effects of flight parameters on internal flow of jet vector nozzle

The complex inner and outer flow-field of solid rocket motor(SRM) secondary hot gas injection vector nozzle is numerically investigated using three-dimensional average Reynolds N-S equations and the k-ε turbulent models.The interaction between free outer flow and internal flow of vector nozzle is investigated.The results show that the flight parameters causes the change of pressure round the nozzle exit and affects the internal flow characteristics of the vector nozzle by means of the action of nozzle boundary layer.The side force has no connection with the flight status parameters when the flight Mach number is supersonic or the back pressure is lesser.On the low attitude and subsonic flow,the side force is reduced rapidly with the increasing of the flight Mach number and depressing of the back pressure.