Mixed convection flow of permeable fluid in a vertical channel in the presence of first-order chemical reaction: Variable properties

Abstract

This paper reports a detailed analysis of the analytical and numerical investigation on mixed convection flow of viscous fluid through a porous medium in the presence of first-order chemical reaction. The combined effect of temperature-dependent viscosity and thermal conductivity on the flow is also studied. The non-Darcy model is applied to define the porous matrix. The effects of viscous and Darcy dissipations are taken into account. The governing equations of continuity, momentum, energy, and concentration which are coupled non-linear ordinary differential equations are solved analytically using the regular perturbation method and numerically using the Runge–Kutta shooting method. Brinkman number and thermal conductivity parameters are used as the perturbation parameters. The velocity, temperature, and concentration distributions are evaluated numerically and plotted in graphs. The effects of variable viscosity, variable thermal conductivity, thermal Grashof number, mass Grashof number, Brinkman number, wall temperature ratio, and first-order chemical reaction on the flow fields are explored. It is found that the variable viscosity parameter enhances the flow and heat transfer whereas the variable thermal conductivity parameter suppresses the flow and heat transfer. For the combined effect, the increase in the porous parameter and chemical reaction parameter results in the reduction of the flow field. The effects of physical parameters such as skin friction and Nusselt number at both the plates are derived and presented in tables. The solutions obtained using the Runge–Kutta shooting method and perturbation method are compared and the solutions agree very well in the absence of perturbation parameters. © 2018 by Begell House, Inc.