Numerical analysis of mono and hybrid nanofluids-cooled micro finned heat sink for electronics cooling-(Part-I)

This study explores the thermohydraulic performance of metallic-oxide and carbon-additives-based mono and hybrid nanofluids-cooled micro pin-fin heat sink by adopting the multiphase Eulerian model. The circular configuration is adopted for micro pin-fins, with the staggered arrangement and constant heat flux applied at the base of the heat sink. The mono and hybrid nanofluids are based on an aqueous solution of Ag, MgO, GNP, MWCNT, Ag-MgO, and GNP-MWCNT mono and hybrid nanoparticles, and a pressure drop (Δ p ) range is applied across the heat sink. The heat transfer and fluid flow performance are evaluated in terms of temperature difference (Δ T ), thermal resistance ( R th ) of the heat sink, average heat transfer coefficient ( h avg ), average Nusselt number ( Nu avg ), pumping power ( PP ), overall performance ( OP ), and performance evaluation criteria ( PEC ), whereas the velocity, temperature, pressure coefficient, and flow streamline contours present the qualitative depiction of flow distributions across the heat sink. The results revealed that under certain Δ p conditions, the GNP dispersed mono nanofluid showed the highest thermal performance of the micro pin-fin heat sink compared to the water as a coolant. The optimal nanoparticle loading (φ) is found between 0.50 % and 0.75 % of GNP nanoparticles. The maximum enhancement in PEC is achieved at 60 % for φ of 0.50 % and 0.75 % for both Δ p of 1120 Pa and 1470 Pa, respectively. At an optimum Δ p , the higher average h avg , Nu avg , and lower R th are achieved.