PBX炸药剪切流动点火性能的实验研究

Experimental Study on Shear-flow Ignition Performance of PBX Explosive

为了研究PBX炸药在完全约束加载和剪切流动加载下的点火性能,采用一级轻气炮对完全约束、剪切流动(不同开孔直径)的实验样弹进行加载,采用高速摄影记录了PBX炸药装药在冲击加载过程中的反应情况,并通过压力传感器测得了加载过程中的应力曲线。使用LS-DYNA软件对完全约束加载和剪切流动加载进行四分之一模型仿真计算,用完全约束下应力参数进行模型参数校核,使用校核的模型参数对剪切流动实验进行计算,获得了炸药在不同条件下的流动速率等参数。结果表明,炸药在剪切流动加载过程中相比于完全约束的装药更容易发生反应;剪切流动加载过程中,PBX炸药是否发生反应,不仅与剪切流动速率有关,而且还与单位时间流量有关,3 mm开孔直径单位时间流量比2 mm开孔直径增加62%。

In order to investigate the ignition performance of PBX explosives under full-constrained and shear-flow loading,the experimental projectile was tested by using a one-stage light gas gun.High-speed photography was used to record the reaction of the PBX explosive charges,and the stress curves in the loading process were measured by pressure sensor.A quarter of the model was used to simulate the full-constrained and shear-flow loading cases by using LS-DYNA software.The stress under full-constrained condition was used for the verification of the model parameters.Further,the model parameters verified was used to calculate the shear-flow loading case,and the flow velocity and other parameters of explosives under different conditions were obtained.The results show that the reaction of PBX explosives occurs more easily under shear-flow loading than the full constrained loading.Not only the shear flow rate but also the unit time flow rate have significant influence on the PBX explosives reaction.The rate of the shear-flow with 3 mm diameter is 62%faster than that with 2 mm diameter.