RDX基PBX药柱烤燃过程的数值模拟

Numerical Simulationof the Cook-off Process of RDX-Based PBX Cylinder

为合理评估炸药的热安全性,采用自主编写的有限元软件—"含能材料动态响应数值模拟软件",对黑索今(RDX)基高聚物粘结炸药(PBX)药柱的烤燃过程进行了数值模拟,实现了炸药多步热分解反应的动力学过程。探索了点火区域各组份质量分数随温度的变化规律。结果表明,400 K时,初级热分解反应开始加速,450 K时次级分解反应明显发生,至460 K时,第三步热分解反应开始加速,气体终产物逐渐积累,当气体终产物质量分数为0.006%时,发生点火。此外,随着升温速率增加,炸药点火时间急剧衰减,中心点温度下降。

To reasonably evaluate the thermal safety of explosive, the cook-off process for RDX-based polymer bonded explosive （PBX） cylinder was numerically simulated using self-written finite element software—dynamic response simulation package for energetic materials. The kinetic process of multi-step thermal decomposition reaction for explosive was realized. Change rule of the mass fraction of each components with temperature in the ignition area was explored. Results show that the primary thermal decomposition reaction at 400 K begins to accelerate. At 450 K, the secondary decomposition reaction occurs obviously. At 460 K, the third step reaction begins to accelerate, the final gas product gradually accumulates. When the mass fraction of final gas product is 0.006%, the ignition occurs. In addition, with the increase of heating rate, the ignition time of explosive is rapidly decayed and the temperature of the center is decreased.