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

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.