Diffusion model for thin layer drying process of corn

Abstract

In this study, single-layer drying behaviour of corn is simulated by liquid diffusion model by using the experimental data for drying temperatures between 40 and 70 °C and for a drying rate of 2 m/s. Three different geometries representing a corn grain, slab, sphere, and cylinder are taken into consideration to specify the geometry which yields best results. The drying curves are obtained by minimizing the sum of squared differences between experimental data and theoretical predictions. Results show that drying behaviour of corn can be modelled reasonably by liquid diffusion model and that the solution based on sphere geometry is in better agreement with the experimental drying behaviour as compared with other geometries. The results also show that the temperature and the movement velocity of moisture from the inner part of corn grains towards the outer part have a quite significant effect on the drying rate.