Effect of Sample Size on Microwave Power Absorption Within Dielectric Materials: 2D Numerical Results vs. Closed-Form Expressions

This study deals with the analytical and numerical solutions of the heat source term because of microwave heating for high and low dielectric materials in ID and 2D configurations. The authors compare closed-form expressions dedicated to microwave power calculation to numerical simulations. A comprehensive and accurate analysis of the microwave power reflected from the surface of the sample is also carried out during microwave heating. The influence of sample length is studied using all original numerical procedure. The study highlights that ID closed-form expressions can be extended to 2D cor figurations in the case of sufficiently high dielectric properties. Examples of heating rate during 2D microwave heating in TE10 mode are finally presented. (C) 2009 American Institute of Chemical Engineers AIChE J, 55: 1569-1583, 2009