【摘要】 根据含锌材料的热起爆机理,建立了在激光作用下炸药点火过程的三维(二维轴对称)有限差分模型,运用此模型对RDX、PETN、HMX和改性B炸药在激光作用下的温度成长过程、温度场分布及点火延迟时间进行了数值模拟。结果表明,三维模型延迟时间计算结果与实验结果较为符合;药柱温度增长主要是在激光照射面上很薄一层药剂内发生;激光的光斑直径、脉宽和炸药的激光吸收系数对点火能量阈值有较大的影响。更多还原

【Abstract】 Based on the mechanism of thermal ignition of energetic materials, a three-dimensional finite difference model describing the process of laser ignition of explosive is established. With the help of this method, the growth process of surface temperature of RDX, HMX and PETN samples and composite B ignited by laser beam and contour of temperature in the samples and explosion induction time of samples are obtained by numerical simulation method. The results show that the calculated values of induction time obtained by three-dimensional model are in agreement with the experimental data. The temperature growth mainly takes place in the surface layer of cylindrical sample irradiated by laser. The beam radius and pulse width of laser and absorption coefficient of the investigated samples to laser are some principal factors affecting the ignition energy threshold.更多还原