{"title":"Effect of Buoyancy Ratio on Non-Darcy Mixed Convection in a Vertical Channel: A Thermal Non-equilibrium Approach","authors":"Manish K. Khandelwal, P. Bera, A. Chakrabarti","country":null,"institution":"","volume":68,"journal":"International Journal of Physical and Mathematical Sciences","pagesStart":1046,"pagesEnd":1051,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/8046","abstract":"This article presents a numerical study of the doublediffusive\nmixed convection in a vertical channel filled with porous\nmedium by using non-equilibrium model. The flow is assumed\nfully developed, uni-directional and steady state. The controlling\nparameters are thermal Rayleigh number (RaT ), Darcy number (Da),\nForchheimer number (F), buoyancy ratio (N), inter phase heat transfer\ncoefficient (H), and porosity scaled thermal conductivity ratio\n(\u03b3). The Brinkman-extended non-Darcy model is considered. The\ngoverning equations are solved by spectral collocation method. The\nmain emphasize is given on flow profiles as well as heat and solute\ntransfer rates, when two diffusive components in terms of buoyancy\nratio are in favor (against) of each other and solid matrix and fluid\nare thermally non-equilibrium. The results show that, for aiding flow\n(RaT = 1000), the heat transfer rate of fluid (Nuf ) increases upto a\ncertain value of H, beyond that decreases smoothly and converges\nto a constant, whereas in case of opposing flow (RaT = -1000),\nthe result is same for N = 0 and 1. The variation of Nuf in (N,\nNuf )-plane shows sinusoidal pattern for RaT = -1000. For both cases\n(aiding and opposing) the flow destabilize on increasing N by inviting\npoint of inflection or flow separation on the velocity profile. Overall,\nthe buoyancy force have significant impact on the non-Darcy mixed\nconvection under LTNE conditions.","references":null,"publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 68, 2012"}