CROSS-BOUYANCY MIXED CONVECTION FROM A CONFINED SEMICIRCULAR CYLINDER IN A CHANNEL

Abstract

The effects of cross-buoyancy on the flow and heat transfer characteristics of a long semi-circular bar in a confined channel have been investigated. The numerical results have been presented and discussed for the ranges of conditions as Reynolds number (Re) = 1 – 40, Richardson number (Ri) = 0– 4, and blockage ratio (β) =16.67% -50% for air as working fluid. The drag coefficient increases with increasing Richardson number and/or blockage ratio. The average Nusselt number is showing a maximum relative enhancement of approximately 8% for the Reynolds number of 40, Richardson number of 4 and for a wall confinement of 16.67%. On the other hand, the maximum relative variation of the coefficient of drag is found to be approximately 55% for the corresponding ranges of settings. Finally, the simple heat transfer correlations are obtained for the proceeding ranges of control parameters. Key words: Semi-circular cylinder; Cross-buoyancy; Blockage ratio; Richardson number; Nusselt number; Drag and lift coefficients and Heat transfer enhancement.