固液火箭发动机矢量控制与喷管效率研究

摘要

According to the characteristics of a hybrid rocket motor,the complex inner flow-field of the secondary gas injection is numerically simulated by using the two-dimensional average Reynolds equations and the k-ε turbulent model.Considering the nozzle efficiency,the influences of the injection position,injection mass flow rate and injection angle on the flow-field of the secondary gas injection are investigated.The results show that the optimal nozzle efficiency and the optimal vector control performance could not be achieved at the same time.The trend of the effect of the injection position on the vector control performance increases firstly and then tends to decrease.The effect of the injection mass flow rate and injection angle on the vector control performance has an increasing trend.Combined with the specific impulse loss,the ideal injection position is located from 1/2 to 3/4 of the nozzle expansion section;the ideal injection mass flow rate is 6％ of the primary mass flow rate,and the ideal injection angle is 140°.%运用平均雷诺N-S方程和k-ε湍流模型,对固液火箭发动机喷管二次燃气喷射形成的复杂内流场进行数值模拟.探究了二次喷射位置、喷射流量和喷射角度对矢量控制性能以及喷管效率的影响.结果表明,矢量控制性能和喷管效率不能同时达到最佳.二次喷射位置对矢量控制性能影响趋势先增加后下降.二次喷射流量和喷射角度对矢量控制性能影响近似呈线性增加趋势.结合比冲损失确定理想矢量控制方案:喷射位置为喷管扩张段的1/2处到3/4处之间的位置;二次喷射流量为主流量的6％;二次喷射角度为140°.