Editorial: Moving boundary problems in multi-physics coupling processes

In many problems such as propagation of crack, fluid-structure interaction, flow in deformable porous materials, material forming process and so on, the boundary of material/ structure or the interface between different materials/structures varies depending on the insitu responses of associating components and environmental factors. Such problems are also named as moving boundary problems, and the time-dependent boundary poses significant challenges to the numerical modelling of such problems as well as the study of inherent mechanisms dominating the evolution of moving boundaries. Severe nonlinearity caused by the moving boundary requires development of advanced numerical algorithms, while interaction of multi-physics behaviors in moving boundary problems such as mechanical, thermal, electrical and even chemical response, necessitates research of multi-physical modelling methodologies. This Research Topic “Moving Boundary Problems in Multi-physics Coupling Processes” collects 16 papers contributing to the experimental, numerical and theoretical research on moving boundary problems of multi-physics processes. While focusing on “Moving Boundary Problems in Multi-physics Coupling Processes,” the selected papers show a good diversity in terms of their research objects, methods and findings. Some contributors have obtained valuable achievements on modelling of cracks. For instance, Ma et al. used discrete element method to establish a numerical model of porous concrete with random circular defects inside, to study the influence of the porosity or size homogeneity of the defects on the mechanical behavior, crack evolution, and acoustic emission (AE) responses. Their findings can aim the understanding of micro-scale mechanism of crack propagation in porous concrete. To accelerate the numerical simulations of fracture, Liu et al. employed degradation function that decouples the phase-field and physical length scales, to reduce the mesh density in large structures. By incorporating the Drucker-Prager failure surface into the phase field model to characterize the tension-compression asymmetry of fractures in rocks, they can capture the crack propagation path in rock materials with a good accuracy and efficiency. Instead of using conventional numerical methods, Lian et al. proposed a novel framework for efficient simulation of crack propagation in brittle materials, whereby the partial differential OPEN ACCESS