Aiding and opposing mixed convection from a cylinder in a saturated porous medium

Numerical solutions are presented for mixed convection from a cylinder embedded in a saturated porous medium. Both aiding and opposing flow conditions are considered. Numerical calculations using the finite difference method with body-fitted coordinates have covered a wide range of governing parameters (i.e., 10 less than or equal to Re less than or equal to100, 0 less than or equal to Gr less than or equal to 400 and Pr = 0.7). The present results agree well with the previous study by Badr and Pop (1988)for flows at a small Reynolds number and a small mixed convection parameter Gr/Re. However, significant discrepancies have been found between the two studies for flows at a high Reynolds number and a high mixed convection parameter Gr/Re. In addition, oscillatory flows are observed for opposing flows at high Gr/Re, which were not revealed in the previous study (Badr and Pop, 1988). Several reasons are offered to explain the discrepancies found.