Optimization of micro pin-fin heat sink with staggered arrangement

The effect of the pin-fin shapes on the overall performance of the carbon nanotube bundles as porous micro pin-fins with in-line and staggered arrangement for the heat transfer and pressure drop is studied using FLUENT 15.0. The results of the study revealed that at 100 < Re < 2000, triangle has the best performance followed by square, rectangle, hexagon and circle in 1 mm height, 15 mm width, and 45 mm length silicon rectangular mini-channel. The staggered configuration gave better heat transfer performance than in-line arrangement at all Reynolds numbers for all shapes with up to 19% thermal improvement but with up to 79% pressure drop differential. On a mini-channel surface with nanotube fins, the nanofluid (0.001 to 1%) increases the thermal performance up to 40% in comparison with water. The best thermal performance enhancement of 106% was obtained by using staggered triangular fins with larger fin height of 0.75 mm, smaller fin width of 0.5 mm, and spacing double the fin width and 0.01% CuO-water nanofluid followed by 103% with 0.01% Al2O3-water in comparison to channels with inline circular fins and water.