嵌金属丝端燃药柱固体发动机水下点火数值模拟研究

为探讨降低固体火箭发动机水下点火初期推力峰值的方法,通过对燃气采用常微分控制方程、对嵌金属丝采用一维传热方程、对端燃药柱采用二维轴对称传热方程、对燃气泡采用球形气泡模型,就嵌金属丝端燃药柱发动机水下点火的工作过程进行了数值模拟研究。算例结果显示,发动机水下点火初期的推力峰值小于稳定工作推力,初始燃面积对推力峰值影响较大,发动机达到稳定工作推力所需时间随药柱直径的减小而迅速减小,发射深度的变化对推力达到稳定状态所需时间影响很小。

Study on numerical simulation of underwater launch for end-burning grain solid motor with embedded wire

In order to make an approach to reducing the initial thrust peak value of underwater launching SRM,underwater launching process of end-burning solid motor was studied by two-dimensional axisymmetric heat-transfer equation used for end-burning grain,one-dimensional heat-transfer equation used for embedded wire and sphere model used for bubble.The numerical results show that the initial thrust peak value is less than steady thrust value,and initial burning surface has a great effect on thrust peak value.The time when the motor reaches steady thrust state reduces rapidly with the decrease of grain diameter,but the change of launching depth has a little effect on the time.