Mixed convection flow in a vertical channel in the presence of wall conduction, variable thermal conductivity and viscosity

Abstract

This study theoretically investigates the effects of variable viscosity, thermal conductivity and wall conduction on a steady mixed convection flow of heat generating/absorbing fluid passes through a vertical channel. One of the channel plates moves with a constant velocity while the other is stationary. The governing flow equations are solved analytically using homotopy perturbation method (HPM). The effects of the thermophysical and hydrodynamics parameters are captured in graphs and tables. It has been observed that, both the velocity and temperature distributions decrease with increase in viscosity and boundary plate thickness near the heated plate while a reverse cases were observed near the cold plate. Increase in thermal conductivity ε decreases the fluid flow near the heated plate. When the boundary plate thickness is increased, the critical value of Gre to onset the reverse flow increases while increase in thermal conductivity reduces the critical value of Gre. It’s also noticed that the skin friction and rate of heat transfer at the heated plate decrease with increase in boundary plate thickness d.

Keywords

• mixed convection
• viscous dissipation
• vertical channel
• boundary plate thickness
• mass flux
• variable viscosity
• variable thermal conductivity