Investigation of flow and heat transfer characteristics in micro pin fin heat sink with nanofluid

• I studied the effect of using nanofluid in micro pin fin heat sink.
• Two nanofluids have been studied (diamond-water and Al2O3-water).
• Three fins shapes (square, triangular and circular) and unfinned heat sink.
• Results show that nanofluid increase the thermal performance and pressure drop.
• The circular fins give higher heat transfer rate compared with other fins.

In this paper a micro pin fin heat sink is numerically investigated with three fins geometries (square, triangular and circular) in addition to the unfinned microchannel heat sink. Nanofluid is used as a cooling fluid, since the flow and heat transfer have been studied with two types of nanofluids (Diamond-water and Al2O3-water) in addition to the pure water. The volumetric concentration of selected nanofluids has been chosen in range (1–4)%. The comparison of hydrodynamic and thermal characteristics of different fin geometries and cooling fluids has been made under the same value of Reynolds number and constant wall temperature thermal boundary condition, the range of Re used is (100–900) to ensure that, the flow remains in the laminar regime. The results obtained indicated that, using of nanofluid instead of pure fluid as a coolant leads to enhanced heat transfer performance by increasing the amount of heat dissipated but it also leads to increased pressure drop for all fins shapes and nanofluids studied.