This paper presents a novel mechanistic explanation for microwave-assisted LIBS to mitigate self-absorption effects. A set of plasma characteristic equations in cylindrical coordinates, including plasma isothermal expansion and modified adiabatic expansion kinetics equations, were formulated. These equations were subsequently coupled with microwave electric field equations to develop a microwave energy-assisted model. These models were employed to numerically analyze the plasma dimensions, velocity, and spatial distribution characteristics of plasma concentration, as well as the energy consump...