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.