Simulation and prediction of radio frequency heating in dry soybeans

Radio frequency (RF) heating is considered as a potential postharvest technology for disinfesting legumes. However, the non-uniformity in SF heating is still a major problem in developing effective SF heat. treatments for pest control and other applications. A computer simulation model was developed with a finite element-based commercial software, COMSOL, to analyse the temperature distributions. Dry soybeans packed in a rectangular plastic container were used to determine the heating uniformity and validate the simulation model using a 27.12 MHz, 6 kW SF system. Both simulated and experimental results showed similar heating patterns in SF treated soybeans, in which corners and edges were more heated and the temperature values were higher in the lower part of the container. The simulation results demonstrated that the RF heating uniformity could be improved using a similar dielectric material around the samples, a smaller top plate area (similar to the sample size), and placing the samples in the middle of the two plate electrodes. The simulation model developed in this study could be applied to improve the SF heating uniformity and to optimise the treatment parameters. (C) 2014 IAgrE. Published by Elsevier Ltd. All rights reserved.