泡沫铝爆炸冲击特性的数值研究

Numerical study on impact properties of Al foam under explosive loading

基于流体弹塑性模型,建立了泡沫铝在爆炸载荷下的冲击特性方程。采用Lagrange差分格式,在均匀网格上对方程进行了离散。编写了数值计算程序,进行了炸药在空中和水中爆炸的一维数值计算。爆炸场中考虑了泡沫铝密度、环境介质对泡沫铝材料冲击特性的影响。结果表明:数值计算结果与理论解、实验实测结果基本吻合,证明所建立的泡沫铝的流体弹塑性本构方程可以用来描述泡沫铝的冲击特性;泡沫铝的密度越低,泡沫铝中的压力峰值越小;在接触爆炸条件下,泡沫铝外侧环境介质的性质对临近环境介质端泡沫铝中的压力影响明显,其中,环境介质若为空气,则临近空气端泡沫铝中的压力呈下降趋势,若环境介质为水,则临近水端泡沫铝中的压力呈上升趋势。

Based on the hydrodynamic-elastoplastic model, the equations were established to character- ize the impact properties of the A1 foams under explosive loading, which were transformed into dis- crete Lagrange difference forms in uniform grid. The shock responses of the A1 foams in water and air were numerically calculated by the self-developed one-dimensional code, respectively. The numerical results are in agreement with the theoretical solutions and the experimental ones. Under the same ex- plosive loading, the lower the density of the A1 foam, the lower the peak pressure in it. And under a contact explosive loading, the properties of the materials surrounding the A1 foam can markedly affect the pressure on its outer side. When air is outside the A1 foam, the pressure in the A1 foam adjacent to air takes on a downward trend. When water is outside the A1 foam, the corresponding pressure takes on an upward trend.