沙墙吸能作用对爆炸冲击波影响的数值分析

Numerical simulation of effect of energy absorption of sand walls under blast wave

由沙袋堆积起来的沙墙对强冲击波具有很好的消波吸能作用,在爆炸实验中对结构有一定的防护作用。沙墙在爆炸冲击波作用下,飞散形成颗粒相,吸收冲击波的能量,降低冲击波对结构的冲击作用。分别使用通用非线性动力学数值计算程序LS-DYNA和自编的多相流程序,计算了某封闭空间中沙墙对爆炸冲击波消波吸能的作用。自编的多相流程序可以计算沙子的飞散,可以考虑对流、辐射传热的吸能作用。LS-DYNA没有这些功能,但是却可以模拟复杂的爆炸与结构相互作用的问题。两种程序对比计算的结果可为使用商业软件LS-DYNA进行类似的复杂数值计算提供参考和修正。

Sand walls, assembled by sand bags, have an effective performance in absorbing energies of blast wave and protecting structure in explosive experiments. Under the blast wave, sand walls scatter, absorb energy of shock wave and reduce the impact of shock wave on the structure. Two different procedures were used to simulate energy absorption of sand walls under blast wave in an airtight space. The first one is LS-DYNA, a universal explicit software for nonlinear dynamics. The other one is a multiphaseflow program, which was programmed in this paper. It can simulate blast wave and sand walls scattering, and calculate convection, radiant heat and energy absorption of sand walls under blast wave. LS-DYNA does not have these functions. Yet it can simulate complicated blast wave and structure interaction. Comparison and analysis of the results of the two procedures may supply some references to the use of LS-DYNA to carry out similar complicated numerical simulations.