长杆和分段杆侵彻的数值模拟

Numerical simulations on long rod and segmented rods penetrating into steel targets

利用ANSYS/LS-DYNA程序,采用Lagrange方法和Johnson-Cook本构模型,对长径比为5的平头钨合金长杆弹、分段体长径比为1的理想分段杆和带套筒的分段杆侵彻半无限厚钢靶进行了三维数值模拟。给出了侵彻过程中典型时刻的物理图像,并对3种杆的侵彻性能进行了比较。结果表明:分段杆侵彻深度的主要贡献在相Ⅲ惯性扩孔阶段而非连续长杆的相Ⅱ准定常侵彻阶段;分段间隔对侵彻深度的增加有显著影响;套筒的贡献主要在于弹坑直径的增加而对侵深影响微小。

Numerical simulations were conducted on the penetration of the long rod with the length-radial ratio of 5,the ideal segmented rod and the segmented rod with a carrier tube into semi-infinite steel targets,respectively,by using the software ANSYS/LS-DYNA3D.The Lagrangian method and Johnson-Cook constitutive model were coupled in the numerical simulations.The von Misese stress contours were given at the typical times during the penetration and the penetration performances of these rods were compared.Comparison shows that the dominant contribution to the depth of penetration(DOP) of the segmented rod is due to the phase Ⅲ non-steady stage rather than the phase Ⅱ quasi-steady penetration stage in the long-rod penetration.The interspacing of the segmented rods has a significant impact on the DOP,while the carrier tube only contributes to the increase of the crater diameter.