基于Forrestal侵彻试验的数值模拟研究

Study of numerical simulation based on penetration experiments of Forrestal

在弹丸侵彻混凝土的数值模拟过程中,材料模型及其相关参数的选取是一项关键且复杂的工作,其原因在于混凝土动力学材料模型参数众多,一般都在几十个以上,而且大多数参数无法通过试验直接获得,有些甚至没有明确的物理意义。通常的办法是通过试验确定少量参数,然后通过数值模拟计算结果反推其他模型参数。鉴于这种情况,非线性动力分析软件LS–DYNA增加了自动生成参数的功能,该成果是由Schwer等在损伤混凝土材料模型的基础上通过大量总结得到的,该特性很大程度上方便了用户在混凝土侵彻数值模拟方面的工作。利用LS–DYNA的该项功能,模拟了Forrestal的部分侵彻试验,并将计算结果同试验数据、经验公式计算结果做了对比分析。结果表明,自动生成参数功能是一种研究弹丸侵彻混凝土问题的简单而有效的办法。

When simulating the penetration of projectile into concrete targets,it is an important and complicated job to find a suitable material model of concrete and its parameters.A kinetic material model of concrete has many parameters which often add up to dozens;most of them cannot be obtained directly by experiments;even some of them are physically meaningless.In common cases,a few parameters can be experimentally measured in advance,and the rest parameters will be obtained by deduction according to computational results.In view of this condition,LS-DYNA provides users with a function which is able to generate parameters of concrete automatically.The function is developed by Schwer et al by means of a great deal of summaries on damage concrete model.It facilitates users to perform numerical simulations about the penetration of concrete to a large extent.In order to check the effectiveness of this function,the numerical simulation of Forrestal’s experiments is conducted,and the comparative analysis is performed for the results from computation,experiments and empirical formulations.The results show that the function is a simple and effective approach to study the penetration problems of projectile into concrete targets.