基于残值函数法的双燃速药柱内弹道分析

Interior ballistic analysis of dual-burning rate propellant grain based on residual displacement function method

残值函数法采用残值函数记录燃面位置,通过惠更斯原理模拟燃面的推移过程。此算法可以准确捕捉由于燃速间断的存在导致燃面的交汇、分离、消失等复杂拓扑结构变化,且不需要进行网格重构,稳定性好。采用残值函数法模拟了双燃速药柱的燃面推移过程,通过数值仿真与试验结果的对比可知,残值函数法准确捕捉了高低燃速推进剂交界面处燃面复杂拓扑结构的变化,解释了双燃速药柱发动机内弹道呈现的转级过程中压强大幅度波动现象的原因。分析了不同燃速交界面位置对发动机内弹道的影响,对药柱的优化设计及成型要求具有指导意义。

The residual displacement function method uses residual displacement function to record the position of the burning surface,and simulates the process of burning surface by Huygens principle.This algorithm can accurately capture the complex topological structure changes such as the intersection,separation,and disappearance of the burning surface due to the existence of the burning rate discontinuity,and it does not require mesh reconstruction and has good stability.In this paper,the residual displacement function method was used to simulate the burning surface transition process of the dual burning rate grains.The comparison of numerical simulation and test results show that the residual displacement function method accurately captures the complex topological structure of the burning surface at the high and low burning rate propellant interface,which explains the reason for the large pressure fluctuations in the transition process of the dual-burning rate grain engine internal ballistics.The influence of the position of the interface of different burning rates on the internal ballistics of the engine is analyzed,which has guiding significance for the optimization design and forming requirements of grains.