Viscous dissipation effects on thermally developing forced convection in a porous medium: circular duct with isothermal wall

A numerical study is reported to investigate the thermal development of forced convection in a circular tube filled by a saturated porous medium, with uniform wall temperature, and with the effects of viscous dissipation included. A theoretical analysis is also presented to find expressions for the temperature profile and the Nusselt number for the fully developed region. The Brinkman model is employed. It is seen that while the developing Nusselt number is significantly dependent on the Brinkman number, the fully developed Nusselt number is independent of the Brinkman number, but both the developing and the fully developed Nusselt numbers, depend on the Darcy number