A coupling method between phase field model and classical linear elastic theory model for static and dynamic fracture

Abstract

Although phase field model has demonstrated excellent performance in dealing with complex fracture, its development and application are hindered by computational costs. In order to reduce the computational time, a novel method is proposed in this paper that couples the phase field model with the classical linear elastic theory model. The solution domain is divided into different subdomains, and corresponding solution scheme is used for each region. The phase field model is solved only in the subdomain where the crack is about to propagate to determine the crack path, while the rest of the solution domain is solved using a linear elastic theory model, allowing for coarser discretization to improve computational efficiency and reduce computational costs. A transition subdomain is included between the two models to ensure that the results from the different models are harmonized at the boundary and to improve convergence. The coupling model is implemented in ABAQUS using user defined element and built-in features, and the model is applied to both static and dynamic fracture analysis. The coupling model is validated through representative examples, and the results show that the presented model can not only effectively portray the static and dynamic fracture processes and accurately describe the crack propagation, but also reduce the computational costs.