基于Visco-SCRAM模型的侵彻装药点火研究

针对弹体侵彻过程中装药的安全性，基于黏弹性统计裂纹力学(visco-statistical crack mechanics, Visco-SCRAM)模型计算装药整体温升、装药裂纹摩擦生热以及弹体装药与壳体摩擦生热，考察这3种机制对装药温升的贡献以及侵彻装药的点火机制，得到了装药点火对应的弹体侵彻临界初始速度。结果表明:(1)装药与弹体内壁摩擦生热对装药温升有一定贡献，随着弹体初始撞击速度的提高，摩擦生热对温升的贡献逐渐增大；(2)黏性、损伤和绝热体积变化导致的装药整体温升对装药点火的作用有限; (3)裂纹摩擦形成热点是侵彻装药点火的物理机制；(4)采用Visco-SCRAM模型可预测低强度、长脉冲载荷作用下的装药点火响应。

Investigation on ignition of an explosive charge in a projectile during penetration based on Visco-SCRAM model

Aimed to the safety of an explosive charge in a projectile during penetration, the visco-statistical crack mechanics (Visco-SCRAM) model was applied to numerically calculate the bulk heat of the explosive charge, the heat produced by the friction between explosive charge cracks, and the heat induced by the friction between the explosive charge and the projectile inner wall. The contribution of the above three mechanisms to the temperature rise of the explosive charge were analyzed, the ignition mechanism of the explosive charge was discussed, and the critical initial penetration velocity of the projectile was obtained corresponding to the ignition of the explosive charge. The investigated results show as follows: (1) the heat induced by the friction between the explosive charge and the projectile inner wall has a certain contribution to the temperature rise of the explosive charge, and this contribution gradually increases as the initial penetration velocity of the projectile increases; (2) the bulk temperature rise produced by the viscosity, damage and adiabatic volume change plays a weak role in the ignition of the explosive charge; (3) the hot spot formation by the friction between the explosive charge cracks is the physical mechanism for the ignition of the explosive charge; (4) the Visco-SCRAM model can be used to predict the ignition responses of explosive charges to low strength and long pulse loads