Adaptive phase-field simulation of crack propagation in brittle materials: COMSOL implementation

In the phase-field model for modeling fracture, a high-resolution mesh is required to accurately capture diffused cracks, leading to high computational costs, especially in three-dimensional problems. In this work, a novel COMSOL application programming interface (API)-based adaptive phase-field method is proposed to improve computational efficiency. Due to the lack of native support in COMSOL for dynamic mesh refinement during the solution process, the code editor in the COMSOL Application Building is utilized to control adaptive mesh refinement during each loading step, and the phase-field value is selected as the indicator to achieve the automatic local refinement of the mesh. The functionality of spatial adaptivity is embedded into COMSOL for the first time. The proposed method directly leverages COMSOL's proven and robust built-in remeshing module and eliminates the need for users to develop or understand complex mesh adaptation code, making the technique immediately accessible to researchers and engineers without specialized programming expertise in adaptive meshing. Validated by several two- and three-dimensional benchmark examples, the proposed model can efficiently simulate quasi-static and dynamic fractures without compromising on accuracy. © 2025 Elsevier B.V., All rights reserved.