A model that describes hydration and heat-mass transport in Portland cement mortar during steam curing was developed. The hydration reactions are described by a maturity function that uses the equivalent age concept, coupled to a heat and mass balance. The thermal conductivity and specific heat of mortar with water-to-cement mass ratio of 0.30 was measured during hydration, using the Transient Plane Source method. The parameters for the maturity equation and the activation energy were obtained by isothermal calorimetry at 23 °C and 38 °C. Steam curing and semi-adiabatic experiments were carried out to obtain the temperature evolution and moisture profiles were assessed by magnetic resonance imaging. Three specimen geometries were simulated and the results were compared with experimental data. Comparisons of temperature had maximum residuals of 2.5 °C and 5 °C for semi-adiabatic and steam curing conditions, respectively. The model correctly predicts the evaporable water distribution obtained by magnetic resonance imaging.

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The aim of this work is the simulation of volumetric strain of tuberous crop during drying. We propose a poroelastic model for predicting the drying kinetics and volume loss of potato cubes during convective drying. The Biot’s theory of poroelasticity was used, which considers the Lamé parameters, Young’s modulus and Poisson’s ratio. Drying kinetics and volumetric strain were modeled and compared versus experimental data. An X-ray microtomograph coupled with image analysis was used to visualize the shape and size of the samples during drying. Drying experiments were conducted at 50, 60 and 70 °C, 20% RH, with an air velocity of 1 and 2 m/s. The drying process was interrupted several times to perform tomographic acquisitions. We found a period of ideal shrinkage, nevertheless, the volumetric strain reveals a kinetic behavior over time. The model computes the volumetric strain, which describes correctly the experimental data obtained by microtomography.

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