Viscous dissipation effect on CuO-Water nanofluid-cooled microchannel heat sinks

Abstract While a microchannel heat sink is known to regulate the temperatures of microelectronics devices, viscous dissipation that originates from work done by viscous forces, might have an impact on the heat convection coefficient from a heated boundary. In this study, the exact solution of the temperature field is established for a fully developed forced convection in a parallel plate channel saturated with a porous medium, subjected to uniform heating at one boundary. Applying the new temperature field in a microchannel heat sink, modelled as a porous medium, this study gauges the effect of viscous dissipation on the electronics cooling device; utilizing a 4% volume fraction CuO-Water nanofluid as a coolant. Assuming a homogeneous model whereby the concentration of the nanofluid is taken as uniform spatially, the two-dimensional temperature field, computed based on the effective thermophysical properties of the nanofluid, reveals that viscous dissipation affects the heat convection at the heated boundary adversely, lowering the heat transfer coefficient by 15.3%, for Reynolds number, R e = 1500 and elevates the temperature gradient in the vicinity of the insulated boundary.