nanofluids, computational fluid dynamics, microchannels, heat transfer
When metal or oxide nano particles are dispersed in fluids to form nanofluids, the particles will improve the thermal conductivity of the fluids. Therefore, it is suggested to use nanofluids as coolant to improve heat-exchanger efficiency. However, the nano particles also cause the increase of fluid viscosity. The present paper has numerically studied the flow and heat transfer of the nanofluids in a microchannel by using Computational Fluid Dynamic method. It is found that although the nano particles enhance the heat transfer of the fluids about certain percent, the nano particles also cause an increase of viscous shear stress, and further causes an increase of the power consumption for delivering the nanofluids through the microchannels.