The current work is focused on laminar flow and heat transfer features in zigzag channels for nanofluid-cooled microelectronic heat sink (MHS). The effects of different configurations of nook, including triangular, rectangular, and circular, in both negative and positive directions are investigated and compared with the flat one. Both experimental and numerical methods are used, and obtained results are compared and discussed. Totally 105 tests in the experimental study and 35 cases in the numerical simulation are investigated. It is observed that the thermal performance of the MHS is improved effectively due to swirl flows generated in non-flat nooks, but the flow resistance is also enlarged. The maximum values of Nusselt number and friction factor are recorded for the MHSs with circular and triangular nooks in negative direction. However, the highest performance factor value of 1.36 is detected for the MHS with triangular nooks in negative direction at the Reynolds number of 700. It is found that adding of 0.1% and 0.4% wt. α-Al2O3 nanoparticles in water as coolant causes an increase in the range of 4.8–13.3% for the heat transfer coefficient and 3.3–9.6% for the pressure drop. Finally, it is concluded that the improvement in the base temperature of MHSs is more significant for higher Reynolds number and nanoparticles weight fraction.

Keywords