空气自由场装药爆炸荷载一维建模数值算法

Study on Numerical Simulation and Engineering Algorithm of Charge Explosion in Free Air

爆炸冲击荷载计算是进行武器毁伤评估和工程防护设计的基础,不同经验公式的计算结果离散度大,而三维模型模拟爆炸过程的效率低。本文提出一维建模数值算法,利用LS-DYNA有限元软件模拟了2种药量球形TNT炸药在自由空气中的爆炸,证明一维模型的计算结果较三维模型更贴近经验值。利用“两步法”将一维结果映射到三维中,能够综合一维与三维模型的优点,建模方便,计算效率及精度高,并能模拟空气冲击波与目标的相互作用过程,在结构与构件毁伤研究领域有良好的应用前景。

The calculation of explosion impact load is the basis of weapon damage assessment and engineering protection design.The calculation results of different engineering algorithms have a large dispersion.The numerical simulation using three-dimensional fluid structure coupling model has a low calculation efficiency.In this paper,a one-dimensional modeling numerical algorithm is proposed.The LS-DYNA finite element software is used to simulate the explosion of two kinds of spherical TNT explosives in free air,and it is proved that the calculation results of one-dimensional model are closer to the empirical value than that of three-dimensional model.The"two-step method"is used to map the calculation results of one-dimensional simulation model to three-dimensional model.This method integrates the advantages of one-dimensional model and three-dimensional fluid structure coupling model.It has the advantages of convenient modeling,high calculation efficiency and high calculation accuracy.It can simulate the interaction process between air shock wave and target,and has a good application prospect in the field of structure and components damage research.