Fully developed laminar free convection flow between two parallel vertical walls—I

In this paper, the natural convection in a non-Darcy porous medium is studied using a temperature-concentration-dependent density relation. The effect of the two parameters responsible for the nonlinear convection is analyzed for different values of the inertial parameter, dispersion parameters, Rayleigh number, Lewis number, Soret number, and Dufour number. In the aiding buoyancy, the tangential velocity increases steeply with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter when the inertial effect is zero. However, when the inertial effect is non-zero, the effect of the nonlinear temperature parameter and the nonlinear concentration parameter on the tangential velocity is marginal. The concentration distribution varies appreciably and spreads in different ranges for different values of the double dispersion parameters, the inertial effect parameter, and also for the parameters which control the nonlinear temperature and the nonlinear concentration. Heat and mass transfer varies extensively with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter depending on Dacry and non-Darcy porous media. The variation in heat and mass transfer when all the effects, i.e., the inertial effect, double dispersion effects, and Soret and Dufour effects, are simultaneously zero and non-zero. The combined effects of the nonlinear temperature parameter, the nonlinear concentration parameter and buoyancy are analyzed. The effect of the nonlinear temperature parameter and the nonlinear concentration parameter and also the cross diffusion effects on heat and mass transfer are observed to be more in Darcy porous media compared with those in non-Darcy porous media. In the opposing buoyancy, the effect of the temperature parameter is to increase the heat and mass transfer rate, whereas that of the concentration parameter is to decrease.

Nonlinear convection in a non-Darcy porous medium

A computational study of the triple-diffusive nonlinear convective nanoliquid flow over a wedge under convective boundary constraints

The steady laminar fully developed flow between two isothermal parallel plates is studied in this paper. The investigation concerns air, engine oil, and water taking into account the variation of all physical properties (μ, k, and p) with temperature. The results are obtained with the direct numerical solution of the governing equations and cover large temperature differences not treated until now. The largest differences of volume flow rate and vertical heat flux from the corresponding constant properties values reach 1568% and 2120% in air, 139% and 247% in oil, and 62% and 55% in water.

Fully Developed Laminar Free Convection With Variable Thermophysical Properties Between Two Open-Ended Vertical Parallel Plates Heated Asymmetrically With Large Temperature Differences

P.C. Sinha

Papers

Fully developed laminar free convection flow between vertical parallel plates