气体二次喷射矢量喷管三维流场计算

Computation of three-dimensional flow field in secondary gas injection for thrust vectoring nozzle

采用三维雷诺平均Navier-Stokes方程和κ-ε湍流模型对气体二次喷射推力矢量喷管复杂干扰内流场进行数值模拟.比较了在不同喷射参数和不同喷管落压比NPR(Noz-zle Pressure Ratio)下的流场特征,分析了这些参数对矢量偏转效率和推力系数的影响.结果表明,二次流喷射位置、喷射角度和二次流质量流量对矢量角的影响相互耦合,喷管达到最大矢量角时,各参数并不能同时达到各自的最优值;矢量角越大,推力系数越小,推力损失越大;矩形喷射口的推力矢量性能优于圆形喷射口;减小喷管落压比可以提高矢量偏转角度.

The complex inner flow-field of the thrust vectoring nozzle based on secondary gas injection was numerically simulated using three-dimensional average Reynolds equations and the κ-ε turbulent models. The influences on the thrust vectoring efficiency and the thrust ratio of different injection parameters and the nozzle pressure ratio were analyzed and investigated. Results indicate that the effects of the position injection orifice, the injection angle and the injection mass flux on the vectoring angle couple each other. When the vectoring angle reaches its maximum value in design conditions, these injection parameters couldn＇t reach their respective best value simultaneously. When the vectoring angle increases, The thrust ratio decreases and the thrust loss increases. The thrust vectoring of the rectangular injection orifice is better than that of the circular injection orifice. The vectoring angle increases with the decreasing of the nozzle pressure ratio.