改进特征线法在水下爆炸正反演问题中的应用

介绍了改进特征线法及其在水下爆炸正反演问题中的应用。将改进特征线法用于TNT炸药球水下爆炸的模拟,并与实验数据和AUTODYN程序的结果比较,结果表明,改进特征线法求解水下爆炸问题具有较好的准确性,且能够捕捉到流场中弱冲击的传播。而后应用改进的特征线法将正问题中的冲击波参数作为初值条件,利用逆序差分格式,对水气界面做反演求解;将反演的水气界面与正问题中的界面作比较,结果显示两者在近场吻合良好。

Application of modified method of characteristics in forward and inversion simulations of underwater explosion

This paper introduces a modified method of characteristics and its application in forward and inverse simulations of underwater explosion. Underwater explosion of spherical TNT explosive is simulated by using the modified method, and the simulated results are compared with those from empirical formula and AUTODYN. The comparisons indicate that the modified method can be used to solve underwater explosion accurately and capture propagation of weak shock of flow field. The modified method is also applied to gas-water interface inversion of underwater explosion. In the inverse simulation, the shock wave from the forward simulation is taken as the initial condition, and inverse difference schemes for inverse simulation are applied. The calculated inversion interface is compared with the forward one, and they are in good agreement in near field.