화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.103, 1144-1154, 2016
Drying of a tape-cast layer: Numerical modelling of the evaporation process in a graded/layered material
Evaporation of water from a ceramic layer is a key phenomenon in the drying process for the manufacturing of water-based tape cast ceramics. In this paper we present a coupled free-flow-porous-media model on the Representative Elementary Volume (REV) scale for coupling non-isothermal multi-phase compositional porous-media flow for the ceramic layer and single-phase compositional laminar free flow for the air above it. The preliminary results show the typical expected evaporation behaviour from a porous medium initially saturated with water, and water-vapour transport to the free-flow region in accordance with the available results from the literature. We elaborate on and discuss the characteristic drying-rate curve for a single layer ceramic, and compare it with that of a graded/layered ceramic. We, moreover, show the influence of the mean diameter of particles of the porous medium (d(p)) which directly affects the intrinsic permeability (K) based on the well-known Ergun's equation of each single ceramic layer on the drying behaviour of a graded/layered ceramic. (C) 2016 Elsevier Ltd. All rights reserved.