An experimental investigation was performed on the single-phase flow and heat transfer characteristics through silicon-based trapezoidal microchannels with a hydraulic diameter of 194.5 μm using deionized (DI) water and γ-Al2O3 nanofluids of volume fractions 0.15 % and 0.26% respectively.The effects of Reynolds number

Prandtl number and nanoparticle concentration on the convective heat transfer characteristics were investigated.The results showed that the pressure drop and flow resistance for nanofluids and DI water were approximately the same

but the Nusselt number of nanofluids increased considerably as compared with that of DI water.With the same pumping power

using nanofluids instead of DI water caused the reduction in thermal resistance.It was also found that Nusselt number increased with the increase in nanoparticle concentration

and the heat transfer enhancement was more obvious at the higher bulk temperature of nanofluids.Based on the experimental data

a dimensionless correlation of Nusselt number was proposed.The results presented in this paper help to guide the design of high efficiency integrated chip cooling system.