Unsteady Mixed Convection Flow of a Reactive Casson Fluid in a Permeable Wall Channel Filled with a Porous Medium

Abstract

In the current paper, we investigate the thermal decomposition in an unsteady mixed convection flow of a reactive Casson fluid in a vertical channel filled with a saturated porous medium. The channel walls are assumed to be permeable with fluid injection through the left wall and suction out of the right wall. There is heat dissipation caused by exothermic chemical reaction within the flow system. The dimensionless form of the momentum and energy equations will be solved numerically using a semi-discretization finite difference method and a fourth order Runge-Kutta-Fehlberg integration scheme. The influence of the Casson fluid parameter, the buoyancy parameter, the porous medium shape parameter, the Eckert number, the suction/injection Reynolds number, Frank-Kamenetskii parameter and the Prandtl number on velocity and temperature profiles, skin friction and Nusselt number as well as the thermal stability criteria are presented graphically and discussed quantitatively. It is revealed that increasing the Casson fluid parameter enhances the flow velocity, the fluid temperature and the skin friction but has a diminishing effect on the wall heat transfer rate. The suction/injection Reynolds number, the porous medium shape parameter and the buoyancy parameter enhance the rate of heat transfer at the channel walls.