【摘要】 为了揭示炸药装药在过载条件下的点火机制，针对炸药抗过载性能评估装置，采用黏弹性统计裂纹(Visco-SCRAM)模型描述炸药的力学与热学行为，将Visco-SCRAM模型以二次开发的方式嵌入LS-DYNA,通过LS-DYNA对炸药装药在过载条件下的响应过程进行计算，通过炸药抗过载性能评估试验装置对DNAN基熔注炸药(RBHL-1)进行测试。结果表明，DNAN基熔注炸药(RBHL-1)的重锤阈值速度为9.0～9.5m/s,当重锤速度超过阈值速度时，炸药药柱上表面发生点火；点火位置位于炸药装药上表面，重锤速度阈值为9.26m/s;数值模拟与试验结果对比表明，Visco-SCRAM模型能够准确预测炸药的点火位置和重锤阈值速度，说明剪切摩擦是抗过载性能评估试验中炸药的点火机制；同时，提高炸药装药质量及炸药中对含能材料的保护能力是提高炸药抗过载性能的重要手段。更多还原

【Abstract】 To reveal the ignition mechanism of explosive charge under overload conditions, based on the anti-overload performance evaluation device, the viscoelastic statistical crack mechanics(Visco-SCRAM) model was used to describe the mechanical and thermal behavior of explosive. The Visco-SCRAM model was embedded into LS-DYNA in the way of secondary development. The response process of explosives under overload conditions was calculated by LS-DYNA. The DNAN-based melt cast explosive(RBHL-1) was tested by the anti-overload performance evaluation device. The results show that the threshold velocity of the hammer is 9.0—9.5 m/s. When the speed of the hammer exceeds the threshold velocity, the upper surface of the explosive will ignite. The ignition position locates on the upper surface of the explosive charge, and the threshold velocity of the hammer is 9.26 m/s. The comparison between numerical simulation and experimental results shows that the Visco-SCRAM model can accurately predict the ignition position and threshold velocity, indicating that shear friction is the ignition mechanism of explosives in the anti-overload performance evaluation test. Meanwhile, enhancing the quality of explosive charge and the protection ability of energetic materials in explosives are effective means to improve the anti-overload performance of explosives.更多还原