| Abstract
| - Two diffusional models were developed for finite cylindrical shapedbodies which take into accountthat mass transfer could have a nonisotropic nature. In the firstmodel, sample shrinkage wasignored; thus, it was solved by the separation of variables method.This hypothesis of constantsample volume was not assumed in the second model, which solved masstransfer equations througha finite difference scheme. The proposed models were applied tothe simulation of drying curves ofgreen beans (Phaseolus vulgaris). Two differenteffective diffusivity coefficients, one radial andthe other axial, as a consequence of the mass transfer through bothdirections, were estimated ineach model. The effective diffusivities estimated with theproposed models varied with thetemperature according to the Arrhenius law. The average percentageof variance explained by thefixed boundaries model was 96.1% and increased to 99.1% whenshrinkage was considered (in themodel solved by a finite difference method). Keywords: Drying models; nonisotropic mass transfer; green bean;shrinkage
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