刚塑性黏结剂的双球壳塌缩热点反应模型

基于Kim的弹黏塑性球壳塌缩模型,假设黏结剂为刚塑性材料,炸药为弹黏塑性材料,建立了刚塑性黏结剂的双球壳塌缩热点反应模型,给出了炸药球壳在冲击压力作用下的速度、应变、温度和化学反应速率的时空分布,以及新的热点反应速率理论表达式.将新的热点反应项与低压下慢反应项和高压反应项结合,得到了炸药冲击起爆三项式细观反应速率模型,并将该模型加入DYNA2D中,模拟了PBX-9404炸药的一维冲击起爆过程,结果表明:该模型不仅可以解释炸药颗粒度和孔隙度对起爆过程的影响,还可以描述黏结剂强度对PBX炸药冲击起爆过程的影响.

Pore-Collapse Model of Double Hollow Sphere with Rigid-Plastic Binders for Hot-Spot Ignition in Shock Explosives

A hot-spot shock ignition pore-collapse model of double hollow sphere has been developed, in which binder was assumed to undergo one type of rigid-plastic deformation and explosive was assumed undergo one type of elastic-viscoplastic deformation. The space and time distributions of the velocity, strain and temperature of explosion were theoretically calculated. A new expression of reaction rate was obtained for the hot-spot ignition. A two-dimensional hydrocode DYNA2D was used to simulate the shock initiation of PBX-9404, with a reaction rate model containing the new hot-spot ignition term, the slow burning term at low pressure and the high-pressure reaction term. The numerical results show that the developed model can not only describe the influence of explosive particle size and porosity on the shock initiation, but also can explain the influence of binder strength in PBX on the shock initiation.