Impact of Linear Heating Profiles on Nanofluidic Convection in Enclosure

Abstract

The present study demonstrates the influence of non-uniform heating on the nanofluidic thermal convection in an enclosure by keeping the mean temperature of heating constant. The non-uniform heating is applied by varying the slope of the linear temperature profile from 0° to 60° at an interval of 15°. The investigation is executed numerically following the finite volume discretization technique. Two different cases are taken into consideration: Case A for linearly increasing temperatures and Case B for linearly decreasing temperatures. The flow structures and heat transfer characteristics are studied for the Rayleigh number from 103 to 106 and the copper-water nanoparticle concentrations from 0 to 0.04, utilizing the streamlines, isotherms, and heatlines. The results reveal that the mean Nusselt number monotonically increases with a rise in slope for all linearly increasing temperature profiles. For the decreasing profiles (Case B), the Nusselt number decreases with a rise in the temperature slope for the lower Rayleigh number (103 and 104); however, a marginal increment is observed at the maximum profile angle for the higher Rayleigh number (105 and 106). This study provides findings helpful for designing thermal devices with the efficient utilization of heating sources.