An automated mesh generation algorithm for simulating complex crack growth problems

In this manuscript, we expand the conforming to interface structured adaptive mesh refinement (CISAMR) algorithm for modeling complex two-dimensional (2D) crack growth problems involving contact/friction along the crack surface and interaction between multiple cracks. The CISAMR algorithm transforms a structured mesh into a high-quality conforming mesh non-iteratively, which is an attractive feature for modeling the evolution of the crack geometry with minimal changes to the underlying mesh structure. To model such problems, the mesh structure is first adaptively refined and updated near the crack tip to form a spider-web pattern of elements for the accurate approximation of the energy release rate and thereby predicting the new crack path. In each step of the crack advance simulation, a small subset of elements in the vicinity of the crack tip is detected using a tree data structure and then deleted/regenerated to simulate the crack growth. The construction of a high-quality mesh with appropriate element aspect ratios in the algorithm allows the use of an explicit dynamic solver, which is essential to simulate the nonlinear response of the problem caused by contact forces along crack faces. Several benchmark fracture problems are presented to study the accuracy of the proposed algorithm, as well as two more complex problems to demonstrate its ability for modeling interaction of multiple growing cracks with one another and with embedded heterogeneities in the domain. (c) 2022 Published by Elsevier B.V.

Automated summary

In this manuscript, an algorithm called conforming to interface structured adaptive mesh refinement (CISAMR) is expanded for modeling complex 2D crack growth problems involving contact/friction and multiple cracks interaction. The algorithm transforms a structured mesh into a conforming mesh without iterations, allowing minimal changes to the underlying mesh structure during the crack geometry evolution. The algorithm achieves accurate approximation of the energy release rate and predicts new crack path by adaptively refining and updating the mesh structure near the crack tip. The high-quality mesh construction enables the use of an explicit dynamic solver to simulate the nonlinear response caused by contact forces along crack faces. The algorithm's accuracy and ability are verified through benchmark fracture problems and more complex problems involving interactions between multiple growing cracks and embedded heterogeneities in the domain.