爆炸冲击波作用于便携式防爆墙的绕射规律

摘要

In order to study the diffraction laws of blast shock waves acting on portable flexible explosive-proof walls, LS/DYNA software was used with the Euler coupling algorithm to analyze effect of the portable explosive-proof wall on diffracted overpressure under conditions of different charge in the same distance, same charge in different distance and same charge in different wall thickness. Simulation with different TNT charges established the formula to calculate peak overpressure near the back wall, and the validity of the calculation model was verified by comparing the reflection overpres-sure at the front wall and diffraction overpressure at the back wall with experimental data. Results show that the diffraction peak overpressure is positively correlated with the charge, and is negatively correlated with explosion-proof wall thickness;the peak overpressure location is away from the back wall by about 2 times the height of the wall. When explosion distance is more than 2. 4 meters, the diffraction peak overpressure at the back wall increases initially, reach to the maximum value at the distance of about 2 times the height of the wall and then decreases. When explosion distance is less than 2. 4 meters, the peak overpressure at the back wall appears at a position about 1 meter away from the wall. The diffraction law is coinci-dent with the experimental results.%为研究爆炸冲击波作用于便携式防爆墙的绕射规律,利用LS/DYNA软件,采用欧拉耦合的方法,分析了TNT药量不同爆距相同、TNT药量相同爆距不同以及TNT药量相同墙厚不同的条件下墙体对环流超压的影响规律,且拟合出了不同TNT药量时墙后超压峰值公式,并通过防爆墙墙前、墙后超压值与已知试验值对比,验证了计算模型的正确性.结果表明:环流超压峰值随着TNT药量的增加而增加,随着墙体厚度的增加而减少,且其超压峰值出现在墙后约2倍墙高位置处;当爆距大于2.4 m时,环流超压的峰值先递增、后递减,最大环流超压发生在约2倍墙高位置;当爆距小于2.4 m时,最大环流超压向墙体移动,距离墙体后面1.0 m左右.验证了其绕射规律与已知研究结果的一致性.