Modelagem e simulação da transferência de calor em alimentos com forma paralelepipedal . Estudo de caso: resfriamento e congelamento de batatas.

Abstract

The freezing foods product is a preservation method wide used in the food industry, because it combines the favorable effect of low temperatures with the conversion of water into ice. The knowledge of the transport properties and the temperature distribution inside these products are of fundamental importance for an optimized project of refrigeration systems. In this sense, this work presents a transient three-dimensional mathematical modeling to describe the heat transfer inside solids with parallelepiped shape including phase change. The governing equation was solved numerically using the fmite-volumes technique and a implicit fully formulation. As application, the methodology was used to predict the heat transfer during the cooling, freezing and post-freezing of french fry. Numérica! results of the 3 temperature in the center of the product were compared to the experimental data reported in the literature and a good agreement was obtained, characterizing the physical validation of O the model. By means of simulation, it was verified influence of the dimensions and the initial moisture content of the potato in the freezing kinetic, that is, how much lesser the dimensions and the initial moisture content of the product, more quickly occur the phase change of the water in its interior. The largest temperature gradients were found in the close surface to the area of the vertex of the solid.