2D orthogonal simulation method for multi-physics field evolution in material-structure heterogeneous rocks under microwave irradiation

Abstract

Due to the significant physical property differences among various diagenetic minerals, it is crucial to characterize the multi-physics field evolution process of microwaves in heterogeneous rocks. To overcome the issues of insufficient refinement in existing numerical studies, this paper proposes a two-dimensional (2D) orthogonal model considering structural-material heterogeneous rocks for the detailed simulation of the strong coupling process of microwave radiation in rocks. Based on a high-fidelity granite model with texture structure, a strong coupled numerical simulation method is developed from both section and facade perspectives. Furthermore, the electrical-thermal-stress-damage physical responses of rocks to microwave radiation are meticulously calculated. The results indicate that both the section model and the facade model exhibit a stress distribution with central compression and surrounding tension, while the damage evolves from the inside out and from the surface inward, respectively. The change in the proportion of the tensile zone and the transformation of the stress properties of the mineral are the response characteristics of damage. The order of mineral damage is biotite, feldspar and quartz, with damage more likely to occur in the feldspar phase. Additionally, the texture structure and physical property differences in heterogeneous rocks are the main driving forces to rock damage. This study provides a novel simulation method for the microwave interaction with rocks and offers new insights into the evolution of multi-physics fields.