空气中TNT爆炸的数值模拟

摘要

To study the of shock wave propagation behavior of TNT explosion in the air and to predict the over-pressure peak in different scale distance,the finite element software LS-DYNA was used to simulate the propagation of shock wave by 7. 5 kg TNT explosion and to reveal the attenuation laws of energy shock wave. Empirical formula was also used to calculate the peak pressure in different scale distance. By comparing the results of numerical simula-tion and empirical formula with experimental data,the results show that the simulation results agreed well with exper-imental data and the error was less than 10%. Compared with the experimental data,the formula put forward by YE Xiao-hua made a smaller error,which was only 0. 66% 3. 5 meters away from explosion center. Result shows YE Xi-ao-hua formula more reliable than Henrych formula. But as the distance increasing,the error increased obviously. Therefore,the formula could be applied when the scale distance was less than 2. 6 m/kg1/3 .%为了研究TNT炸药爆炸产生的冲击波在空气中的传播规律和预测不同比例距离的超压峰值，应用 LS-DYNA有限元软件模拟了7.5 kg TNT爆炸的冲击波传播过程，揭示其能量衰减规律。并用2种经验公式计算不同比例距离的冲击波超压峰值。对数值模拟结果、经验公式结果和已有的实验数据进行对比。结果表明：数值模拟结果与实验数据吻合较好，误差在10％以内，证明了计算模型和参数的合理性。2种经验公式，叶晓华推荐的经验公式与实验数据的误差相对较小，距爆心3.5 m处，误差仅为0.66％。说明叶晓华公式相比Henrych公式更为可靠。但随着爆距的增大，误差也明显增大。建议此公式在比例距离小于2.6 m/kg1/3时采用。