Effects of heat sink structure on heat transfer performance cooled by semiconductor and nanofluids

On account of the low heat dissipation problem of common cooling systems, an experimental system with enhanced structures was set to improve the heat transfer of heat sink cooled by semiconductor and TiO2-water nanofluids. The influences of structures (smooth surface, metal foam with PPI=30, cylindrical bulge (height: H=2 mm, staggered arrangement), cylindrical groove (depth: D=2mm, staggered arrangement)), nanoparticle mass fractions (omega=0.0-0.5 wt%), input power of the semiconductor (P=2W, 4W, 6W), and Reynolds numbers (Re=414-1,119) on the flow and heat transfer properties of TiO2-water nanofluids were studied. The compositive thermal and hydraulic properties of the enhanced technologies were analyzed by thermal efficiency. Results indicated that the combination of semiconductor and metal foam shows the most excellent performance compared with other combinations and it can be enhanced by 48.1% at best. Nanofluids with omega=0.4 wt% display the best cooling capacity instead of the highest concentration. The cooling effect shows an increasing trend with the input power of the semiconductor.