Microwave Heating Multiphysics Computation of Moving Complex-Shaped Samples Based on Ray Casting Method

Moving samples can improve the heating uniformity during microwave heating, but it is challenging to compute moving complex-shaped samples. This article proposes a microwave heating computation method for moving complex-shaped samples based on boundary recognition. First, a boundary recognition method based on ray casting is proposed to determine whether mesh points are located inside or outside of the complex-shaped samples. The electromagnetic parameters of the simulation domain are set as functions of time and space to perform microwave heating computations. Second, the electric field distribution and temperature distribution obtained by the proposed method and the implicit function and level set methods (IFLSMs) are compared using a regular-shaped sample. The results show that the computation results of the two methods are consistent. In addition, for complex-shaped samples, the electric field distributions of the proposed method and discrete position method are compared, and experiments are carried out to verify the proposed method. The average errors of the center point temperatures of three samples with different shapes are 2.7%, 2.9%, and 2.5%, which means that the proposed method can be applied to compute the microwave heating of complex-shaped samples accurately. Finally, the effect of different motion modes of rising, rotating, and both rotating and rising on the heating performance of complex-shaped samples is further explored.