Coupled DEM/CFD simulation of heat transfer in a generic grate system agitated by bars

Coupled DEM/CFD simulations are compared to experiments with agitated spherical particles (10 mm in diameter) on a generic grate and exposed to a transient heat-up by a hot air flow. A video camera and a thermographic system monitor the experiments. Because the particles show Biot numbers > 1 the radial temperature distribution within the particle has been calculated by solving the unsteady one-dimensional differential equation for heat conduction in the DEM simulations. A visual comparison of the heat-up of the particles and particle transport within the bed shows a good agreement between simulations and experiments. In addition, local minimum, maximum and average particle surface temperatures in different layers of the particle bed are calculated. Experimentally measured temperature gradients over the particle bed height are in very good agreement to DEM/CFD simulations.