Simulation of three-dimensional infrared drying using a set of three-coupled equations by the control volume method

A control volume formulation for the solution of a set of three-way coupled heat, moisture transfer, and pressure equations with an infrared source term is presented in three dimensions. The solution procedure developed uses a fully implicit time-stepping scheme to simulate the drying of potato during infrared heating in three-dimensional Cartesian coordinates. Comparison was made between the simulation results of the three-way coupled equations with the two-way coupled set of equations and the experimental results from two different infrared heating systems constructed for this purpose. Simulation indicated that the three-way coupled model predicted the temperature and moisture contents better than the two-way coupled heat and mass transfer model. High-moisture regions in the three-dimensional discretized space were also identified. The maximum deviations between experimental and simulation results were 8.0° C in temperature for potato drying and 10% (d.b.) for moisture predictions. The overall predictions agree well with the available experimental data and show a good potential for application in grain and food drying.