基于SPH方法的聚能射流侵彻混凝土靶板数值模拟

Numerical simulation on penetration of concrete target by shaped charge jet with SPH method

在完全变光滑长度SPH(smoothed particle hydrodynamics)方法的基础上,利用F.Ott等提出的修正SPH方法处理在求解多介质大密度问题时的数值不稳定性问题,运用Holmquist-Johnson-Cook本构模型处理混凝土在冲击载荷下的变形和损伤问题,对聚能装药射流侵彻混凝土靶板的过程进行了数值模拟,同时利用LS-DYNA非线性有限元程序进行对比,分析了2种方法得到的混凝土von Mises应力变化、射流头部特定节点处的速度变化及裂纹演变,验证了SPH方法的准确性。分析了另外2种不同尺寸的靶板在射流侵彻作用下的破坏形式,结果符合射流侵彻物理规律,表明该方法适合模拟聚爆炸与冲击等大变形破坏等问题。

On the basis of the smoothed particle hydrodynamics（ SPH） method with fully variable smoothing lengths,the modified Ott-Schnetter SPH method was used to cope with the computational instability in the large density gradient problems. The Holmquist-Johnson-Cook constitutive model was used to cope with the deformation and damage of concrete under impact. By comparing with the corresponding ones simulated by the non-linear finite element program LS-DYNA,the changing courses of the von-Mises stress and cracks in the concrete targets,and the velocities at the some special points of the jet head were analyzed,which proved the feasibility and accuracy of the SPH method. Other two concrete plates with different sizes penetrated by shaped charge jets were also simulated. The results are in good agreement with the physical principle. So this method can be used to deal with the multi-material and large deformation problems such as detonation and impact.