仿珍珠母陶瓷/聚合物复合板抗弹性能模拟的高精度FEM-SPH耦合法及其应用研究

仿珍珠母陶瓷/聚合物复合材料模仿珍珠母的内部结构和增韧机制，能克服陶瓷韧性差的缺陷，在防护结构中应用前景很好。其抗弹性能研究处于起步阶段，以FEM模拟为主，但FEM模拟存在网格畸变、精度不高等缺点。且目前的研究局限于刚性弹侵彻下的抗弹性能，对弹体变形、形状和入射条件的影响缺乏深入认识。为此，本项目首先提出面-面型SPH接触算法，提高SPH的接触计算精度，开发模拟侵彻问题的改进SPH法。然后，研究弹体侵彻仿珍珠母陶瓷/聚合物复合板的FEM-SPH耦合建模技术，构造耦合模型中各类接触界面的统一面-面型接触算法及粘结界面算法，嵌入相关本构模型和界面失效准则，开发模拟仿珍珠母陶瓷/聚合物复合板抗弹性能的高精度FEM-SPH耦合法，克服FEM的缺陷，并通过抗弹性能试验验证其可靠性。最后，应用其模拟变形弹侵彻下仿珍珠母陶瓷/聚合物复合板的抗弹性能，系统地分析靶板内部结构、弹体形状和入射条件的影响。

Nacre-like ceramic/polymer composites mimic internal structures and toughening mechanisms of nacre. They can overcome the poor toughness of ceramic and have promising potential in application to protective structures. The study of their ballistic performance is still in the early stage and mainly employs finite element method (FEM)–based simulation. However, FEM simulation suffers from deficiencies such as element distortion and poor accuracy for the study. Besides, existing studies are limited to ballistic performance under penetration of rigid projectiles, and effects of projectile deformation and shape as well as impact condition are not clearly explored. In this project, a surface-to-surface contact algorithm is firstly proposed to improve the contact treatment in smoothed particle hydrodynamics (SPH) method, and a modified SPH method for penetration simulation is obtained. Then, techniques for establishing FEM–SPH coupling model of nacre-like ceramic/polymer composite plates penetrated by projectiles are studied. A general surface-to-surface contact algorithm and a cohesive interface algorithm are constructed to treat all kinds of contact interfaces and cohesive interfaces, respectively, in the FEM-SPH coupling model. Relevant constitutive models and failure criterion for cohesive interface are implemented. A FEM-SPH coupling method of high accuracy is developed for simulating ballistic performance of nacre-like ceramic/polymer composite plate to overcome the deficiencies of FEM. The reliability of the developed method is validated by ballistic performance test. Finally, the FEM-SPH coupling method is applied to simulate ballistic performance of nacre-like ceramic/polymer composite plates under penetration of deformable projectiles. Effects of internal structure of target plate, projectile shape and impact condition are systematically analyzed.