Modelagem matemática da difusão líquida durante a secagem do trigo.

Abstract

: The objective of the present work was to adjust the liquid diffusion model to the wheat drying curves and to determine the diffusion coefficients for different controlled temperature conditions. Wheat grains with initial moisture of 0.32 d.b. were used. The drying process was conducted under different controlled temperatures (25, 35, 45 and 55°C) and Relative Humidity of 55± 1%. The liquid diffusion mathematical model was used, with analytical solution for cylindrical geometric shape and eight terms approximation. Based on the obtained results, it can be concluded that the liquid diffusion represents satisfactorily the wheat drying kinetics under different tested drying air conditions for wheat. The diffusion coefficient increases as the drying air temperature increased presenting values from 8,3306 x 10-11 to 41,0977 x 10-11 m2.s-1 for the temperature range tested.