The simulation of microwave heating of wood using a rectangular wave guide: Influence of frequency and sample size

Microwave heating–drying of wood using a wave guide is a relatively new area of research. In order to gain insight into the phenomena that occur within the wave guide together with the temperature distribution in the wood, a detailed knowledge of absorbed power distribution is necessary. In this paper, a two dimensional numerical model is developed to predicted the distribution of electromagnetic fields (TE10-mode), power and temperatures distributions within wood located in rectangular wave guide. A three dimensional finite difference time domain (FDTD) scheme is used to determine electromagnetic fields and absorbed power by solving the transient Maxwell's equations, and finite difference method is used to obtain unsteady temperature profiles. Temperature dependence of wood dielectric properties is simulated through an iterative process. The simulations are performed illustrating the influence of irradiation times, working frequencies and sample size. The presented modeling is used to identify the fundamental parameters and provides guidance for microwave drying of wood.