NUMERICAL AND EXPERIMENTAL NETWORK STUDY OF EVAPORATION IN CAPILLARY-POROUS MEDIA - DRYING RATES

Experiments of evaporation are carried out in a two-dimensional microm odel under quasi-isothermal conditions. Three basic cases are investig ated: in the absence of gravity forces, in a stabilizing gravity field and in a destabilizing gravity field. The drying rates are measured a nd compared to the results of numerical pore network simulations. Whil e an excellent agreement between the simulations and the experiments w ere found in a previous study in terms of phase distributions, the agr eement is only qualitative as far as drying rates are concerned. The p oor quantitative agreement between the simulations and the experiments is explained by the existence of roughness and corner flows within th e micromodel during drying. These liquid him flows are not taken into account in the simulations. (C) 1998 Elsevier Science Ltd. All rights reserved.