关键词: 近场有限元法, 断裂损伤, 改进栅格法, 非结构网格划分

Abstract: Material failure has a direct impact on the reliability and safety of the components of engineering equipment. Accurately predicting fracture behavior using traditional measurement techniques is challenging. Peridynamics (PD) is an integral nonlocal continuum mechanics theory that effectively simulates material fracture failure. However, PD does not rely on pre-generated mesh to construct the governing equations. Nevertheless, it suffers from low computational efficiency when solving large-scale problems. This paper presents an improved grid-based mesh generation technique based on bond-based PD finite element method. An improved grid-based mesh generation method is proposed for complex geometries with arbitrary cracks. Additionally, an efficient orthogonal quadrilateral-dominated automatic surface mesh generation scheme is developed. The boundary fitting algorithms are adopted to achieve high-quality entity boundary fitting, which successfully solves the problem of entity boundary fitting of the traditional out-side-in mesh method. In addition, peridynamics-based finite element method combines the advantages of bond-based PD and unstructured mesh generation techniques. This method fully exploits inherent advantages of PD in representing the non-local action effect and discontinuous deformation characteristics of materials, while maintaining the characteristic of fast node traversal of the finite element method. Combined with the improved grid-based mesh generation method, numerical examples have demonstrated the effectiveness and reliability of the peridynamics-based finite element method (PeriFEM) in conducting damage analysis of finite width plates, L-shaped plates, double-notched plates and centrally notched disks.

Key words: peridynamics-based finite element method (PeriFEM), fracture damage, improved grid-based method, unstructured mesh generation