Effect of different parameters on double diffusive free convection flow from a vertical plate under convection boundary condition

This paper investigates combined heat and mass transfer by free convective flow of a vertical flat plate with thermal convective boundary conditions. Governing equations for the velocity, temperature and concentration has been solved numerically by using an efficient Runge–Kutta–Felberg fourth–fifth order numerical method with shooting technique under Matlab 2013 software. Uddin group theory has been implemented to derive suitable similarity transformations in order to render the governing conservation equations into a system of nonlinear ordinary differential equations. The effect of different values of parameters Prandtl number, Biot number, Schmidt number, Richardson number and buoyancy ratio has been analyzed. A comparison with previously published work is performed and the results are found to be in good agreement. The results show that the fluid velocity and temperature profiles fall with rising of Prandtl number but concentration behavior is just the reverse, and Increasing Biot number leads to increase the shear stress. Result indicate that Friction factor rises with buoyancy ratio and Schmidt number increases shear stress, wall couple stress and Nusslet number decrease, the opposite is the case for the Sherwood number. Also a rise in Richardson number increases skin friction, but reduces both concentration and temperature magnitudes.

کلیدواژه ها:

Convective boundary condition ، Mixed convection ، Prandtl number