Multiphysics Modeling of Warm-Air Drying of Potatoes Slices

S. Sandoval Torres[1], A. de Lourdes Allier González[1], L.L. Méndez Lagunas[1]
[1]Instituto Politécnico Nacional, CIIDIR, Oaxaca, Mexico
Published in 2012

In this work we solve a model to simulate the drying of potatoes slices. The model considers both the transport of free and vapor water by applying a mechanistic approach. The critical moisture point (CMP) was considered, since it is a transition zone and it represents the point where water saturation is near from cero and hygroscopic domain begins. The CMP divides the hygroscopic and non-hygroscopic domain of the material. At values above CMP free water is removed, and bellow CMP bound water and water vapor are removed. On one hand, to simulate free water transport we take into account the capillary diffusivity term, and by other hand, to simulate water vapor evacuation we consider the desorption isotherm of potatoes. The sorption isotherm depends on local moisture content and temperature. The model solves the primary unknown’s moisture content, temperature and dry-air density.