Heat transfer in MHD square duct flow of nanofluid with discrete heat sources

Abstract

The effect of thermal and solutal buoyancy induced by a discrete source of heat and mass transfer in a square duct under the influence of magnetic field, especially at the turbulent regime for the first time is reported. Al2O3/water nanofluid is used with constant heat flux from three discrete heat sources. In the present study, the effects of Reynolds number (100 to 3000), particle volume fraction (0 to 2%) and magnetic field (Ha = 10 to 90) on the Nusselt number, pressure drop and wall temperature (at the axial and height directions) are represented graphically and discussed quantitatively. Two percent Al2O3-water nanofluid under Ha = 10 can produce 81% increase in Nusselt number with only 60% increase in pressure drop when compared to base fluid at Re = 100. Four percent enhancement in nanofluids cooling effect in the vicinity of a centre of the final heat source can be utilized in hot spots cooling.