Discrete heating of opposing mixed convection heated at bottom of annulus

Opposing flow mixed convection occurs due to the fluid being forced to flow in opposing direction as that of rising fluid due to thermal buoyancy. This paper undertakes the investigation of heat transfer in an annular porous medium because of mixed convection opposing flow from top of the cylinder. The fluid velocity designated as Vo is applied from top of the cylinder in negative gravitational direction. The governing equations are converted into dimensional form having the Peclet number. The inner radius of the annulus is heated in three segments as 20%, 35% and 50% of the annulus height in such a way that the heater always coincides with the bottom of cylinder.