平纹织物三维细观几何模型和织物防弹实验的有限元模拟

3D Meso-geometrical Model of Plain Weave Fabric and Finite Element Modeling Under Ballistic Impact

建立了平纹织物的三维细观几何模型,利用LS-DYNA有限元软件模拟了弹丸冲击的条件下,单层芳纶织物的响应过程。模型的几何形状参考了平纹织物的截面显微镜照片,使建立的模型更加准确,更接近平纹织物真实的结构。纱线模型选用正交各向异性材料,材料参数和失效条件均参考真实的Kevlar织物,并考虑纱线和纱线之间以及纱线和弹丸之间的摩擦。模拟中,通过设定弹丸的撞击速率Vs,得到剩余速率Vr,并由此计算单层织物的弹道极限速率V50。结果表明:织物的变形过程和失效形式在模拟中得到细致的显现,模拟所得结果V50和织物的失效形式与实验结果的一致程度较好。

The 3D mesoscopic geometrical model of plain weave fabric was built. A commercially avail- able finite element analysis code （LS-DYNA） was used to model the dynamic response of fabric under the condition of ballistic impact of a rigid sphere. The geometry of the model was based on the photo- micrographs of sectioned laminates, which helped us define the accurate and real yarn geometry. Yarns were modeled as orthotropic elastic and the parameter and the failure criteria were referred to the actual Kevlar fabric. Friction between the yarns and sphere was considered. The residual velocity was obtained by setting the striking velocity. The ballistic limit velocity V50 of the single fabric was calculated. Results indicate that the delicate deformation process and failure mechanism of the fabric are finely captured, and good agreements between simulation and the test data are obtained in terms of the V50 and the failure mechanism of the fabric.