Conjugate mixed convection laminar non-Darcy film condensation along a vertical plate in a porous medium

This study numerically investigates the coupling of the wall conduction with laminar mixed-convection film condensation along a vertical plate within a saturated vapor porous medium. The Darcy-Brinkman-Forchheimer model is utilized to treat the flow field and the effect of heat conduction across the wall is taken into account. The governing system of equations with their corresponding boundary conditions are first transformed into a dimensionless form by a non-similar transformation and the resulting equations are then solved by the cubic spline collocation method. Of interest are the effects of the conjugate heat transfer parameter ii, the Jakob number Ja, the Peclet number Pe and the inertia parameter Gamma on the fluid-solid interfacial temperature distribution and the local heat transfer rate. The results indicate that the effect of wall conduction has great influences on the filmwise condensation heat transfer, and is to reduce the local heat transfer rate as well as the dimensionless interfacial temperature in comparison with the isothermal Flare case. It is found that the local heat transfer rate increases with a decrease in the Jakob number, the Peclet number, and the inertial parameter or an increase in the conjugate heat transfer parameter. In addition, the overall surface heat transfer rate for different values of A and Ja are also obtained. (C) 2001 Elsevier Science Ltd. All rights reserved.