O modelo difusivo para avaliar a influência dos tecidos internos dos grãos de cevada

Abstract

Drying is the simultaneous transfer of heat and mass between a material and air. Having the influence of several variables throughout the process, a mathematical description of these phenomena becomes somewhat complex. Aiming to contribute with knowledge in the development of the drying process, this work aims to understand the influence of protective fabrics on moisture transport during the drying of barley grains. For that, experimental data, available in the literature, were used for whole and polished grains, for which modeling was carried out based on the thin layer theory, using the analogy of Fick's Law. Thus, it was possible to obtain the effective diffusive moisture coefficients of 4,124x10-09 m²/s and 8,248x10-09 m2 /s for the whole and polished grains, respectively, from a good fit of the model to the experimental data. From these results and the graphic analysis, it was seen that the whole barley grains have a slower moisture transport kinetics when compared to grains without external tissues, because these structures have the morphological function of protecting the energy reserve of the grain ( endosperm) and the embryo..