基于气体发生剂的子弹药气囊抛撒数值模拟研究

摘要

针对以气体发生剂为动力源的子弹药气囊抛撒数值模拟问题,采用LS-DYNA有限元软件,建立了以燃气质量流率-时间历程曲线为输入条件的子弹药气囊抛撒任意拉格朗日-欧拉流体与固体耦合计算模型,提出了采用内弹道理论和密闭爆发器试验求解气体发生剂名义燃速方程和燃气质量流率-时间历程曲线的方法.通过对装填不同药量氮气发生剂的典型子弹药气囊抛撒结构数值模拟,得到该抛撒结构下子弹药出舱速度、过载峰值随气体发生剂药量的变化规律,验证了弹箍对子弹药抛撒的促进作用.试验验证结果表明,所建立的数值模拟计算方法能较好地预测子弹药抛撒运动参数.%For the numerical simulation of submunition dispenser with gas generant and airbag,a model of airbag dispersing is built by using software LS-DYNA and solid-liquid coupling ALE algorithm,in which the mass flow rate of gas is considered as the input parameter of numerical simulation.On the basis of interior ballistic theory and closed bomb vessel experiment,the nominal combustion rate equation of gas generant and the mass flow rate equation are presented.The typical structure of submunition dispenser fileed with different amount of gas generant is simulated to obtain the velocity of submunition dispensed from airbag and the change of overload peak with the amount of gas generant.The simulated results are in agreement with the test results.The results show that the proposed method could be used to predict the velocity and acceleration of submunitions in practical tests.