Study on heating characteristics of granites with different sizes in microwave field

Abstract

Studying the heating characteristics of rocks in a microwave field is fundamental to exploring the mechanism of microwave rock breaking. Therefore, a heterogeneous granite model was established using COMSOL Multiphysics to deeply analyze the specific influence of rock size on rock heating characteristics in a microwave field. The results show that with the increase of rock size, the heating rate of rock exhibits a fluctuation characteristic. This phenomenon occurs because changes in rock size leads to variations in both the magnitude and spatial arrangement of electric field intensity. Further analysis of the electromagnetic loss of granite reveals that increasing rock volume can significantly enhance microwave energy utilization ef?ficiency. Additionally, biotite occupying only 8% of the rock volume, absorbs over 55% of the microwave energy, highlighting the significant impact of biotite content on the heating characteristics of granite.