A numerical study was performed to determine evaporation rate from the surface of a binary mixture of ethanol and iso-octane flowing in an inclined 2D channel. The liquid and gas phases are flowing in counter-current direction. VOF multiphase model was used to model stratified two-phase flow. The vapour/liquid equilibrium pressure was calculated using UNIFAC model. Mass transfer contributions from each component evaporating into the carrier gas was calculated and source terms were accordingly implemented in the continuity, momentum, energy and species equations. A parametric study with different inlet and exit conditions was performed. (c) 2008 Elsevier Ltd. All rights reserved.