爆炸荷载作用下浮法玻璃碎片飞散的模拟

Simulation on Splash of Float Glass Fragments under Blast Loading

高速飞行的玻璃碎片会对人员造成极大的危害。对爆炸荷载作用下浮法玻璃碎片的飞散进行了模拟研究。首先采用DYNA有限元软件,在选用合适的玻璃材料模型后,对节点分离法模拟裂纹开裂的可行性进行验证。结果表明,该方法可以反应裂纹开裂的特性和玻璃材料的脆性。接着采用上述方法对爆炸荷载下玻璃碎片飞散进行了模拟。通过模拟发现玻璃在爆炸波作用下迅速发生破碎,并产生正向运动的飞散碎片,还会产生部分反向运动的玻璃碎片。模拟飞散破坏情况基本与实验高速摄影结果一致,得到的碎片飞散速度也与试验值吻合较好。最后分析得到了玻璃碎片的速度累积概率曲线。通过该曲线可以方便地得出碎片飞散速度的范围,判断出反向运动碎片的比例。对比不同TNT当量的碎片速度累积概率曲线发现,正向运动的玻璃碎片速度随着TNT当量的增大而增大,而反向运动碎片的比例不断减小,但却不等于零。这说明总会有少量的碎片反向运动,这一比例最终稳定在3%左右。

High-speed glass fragments would cause great harm to people. The splash of float glass fragments under blast loading is simulated. DYNA is used to verify the feasibility of that the MNS( method of node separation) is used to simulate the cracking of an appropriate glass material model. The validation results show that the MNS could characterizes the cracking characteristics and brittleness of glass. The splash of float glass fragments under blast loading is simulated. It is found that the glass is quickly broken under the action of blast wave,the glass fragments fly forward at a certain speed,and some fragments fly backward. The simulation results consist with those of experiments. The velocity cumulative probability curve of the fragments is obtained at last. The splashing speed range of fragments is obtained,and the proportion of fragments which splash in reverse direction is determined. By comparing the velocity cumulative probability curves of fragments under different TNT equivalents,it is found that the speed of fragments moving forward increases with the increase in TNT equivalent,but the proportion of reversely moving fragments decreases and is not equal to zero.