Modeling Heat and Mass Transfer in Laminar Forced Convection in a Vertical Channel: Influence of Reynolds Number

Abstract

The phenomena of heat and mass transfer are of considerable interest in the field of energy. We present in this work a numerical study of the heat and mass transfers in laminar forced convection in a vertical channel, whose wet walls interact with the external environment. Based on simplifying assumptions, the flow, whose thermo-physical properties depend on temperature and relative humidity, was modelled by the Navier-Stokes equations and the flow conservation equation. The finite volume method was used to discretize the equations and the resulting algebraic equation systems were solved using Thomas' and Gauss' algorithms. The influence of the Reynolds number on thermal and mass transfers was mainly investigated. Numerical simulations with Reynolds numbers of 500, 1000 and 1500 have allowed a detailed study of the flow structure as well as thermal and mass fields. The numerical results obtained, presented in isotherms, iso-concentrations, Sherwood and Nusselt numbers, reveal the important role of the Reynolds number in heat and mass transfers in a vertical channel. The rates of these transfers at the entrance to the channel differ from those at the exit.