动态加载下高聚物粘结炸药中椭圆孔洞坍塌引起的热点温度及其半经验解析表达

Hot Spot Temperature Resulting from Elliptical Void Collapse in PBX under Dynamic Loading and Its Semi-empirical Analytical Expression

为获得高聚物粘结炸药内部的热点信息,对其内部椭圆形孔洞在激波载荷作用下的坍塌过程进行了研究。通过相似分析和中尺度模拟,分析冲击强度和孔洞几何形状(孔洞尺寸、位置和伸长状态)对热点温度的影响。结果表明:在一定的冲击强度及特定位置和伸长状态下椭圆形孔洞产生的热点温度可高达2 990 K,比同面积下圆孔洞产生的热点温度(1 946 K)高54%,可使炸药更加敏感;通过使用中间渐近、完全和不完全相似的相似性分析,得到由椭圆形孔洞在激波载荷作用下坍塌所导致的热点温度半经验解析表达,以表征热点温度与冲击强度和孔洞几何形状的关系,热点温度的理论预测结果与数值结果吻合良好。

The collapse process of elliptical void in a plastic bonded explosive(PBX) under shock loadings is comprehensively investigated through similarity analysis and mesoscale simulation,and the effects of the shock intensity and the void geometry,including the size,position and elongated state,on the hot spot temperature are analyzed.The hot spot temperature generated by an elliptical void can reach up to 2 990 K under the conditions of a certain impact strength,a specific position and elongated state,which is about 54% higher than the hot spot temperature(1 946 K) generated by a circular void in the same area,and this may cause explosive more sensitive.By using similarity analysis of intermediate asymptotics,complete similarity and incomplete similarity,a semi-empirical analytical expression for the hot-spot temperature resulting from the collapse of elliptic void subjected to a shock load is presented to predicate its dependence upon the shock intensity,the void geometry as well as the physical properties of the explosive,and the predicted results are in good agreement with the numerical results.