A Mathematical Modeling Study of Hot Air Drying for Some Agricultural Products

The aim of this paper is to investigate the applicability of simplified mathematical drying models from the research works proposed by several investigators to the drying of some agricultural products. Drying experiments were conducted using a conventional biomass longan dryer at drying air velocity 1.34 m/s and drying air temperature 80oC for red chili peppers, 70"C for lemon grass and 60"C for leech lime leaves. Drying curues obtained from the experimental data were then fitted to the empirical drying models. Thirleen different mathematical drying models were compared according to their coefficients of comelation in order to estimate the drying curves of those products. The results have shown that among the models, the Midilli et al. model was found to be the best model for describing the drying behavior of red chili peppers and leech lime leaves, whereas the Wangh and Singh model was the most suitable for lemon grass.