Numerical Investigation of the Effects of Al2O3 Nanofluid on the Thermohydraulic Performance of Fractal Microchannel Heat Sink

Microchannels when employed with nanofluid as working fluid lead to better thermal management of high heat generating devices. Dissipation of high heat flux remains the main challenge along with the maintenance of temperature uniformity. In the current paper, fractal microchannels heat sink (FMCHS) is investigated numerically using finite volume approach. Thermohydraulic performance of FMCHS with water-Al2O3 nanofluid is studied, and its performance is compared with water as working fluid. Reynolds number at the inlet is varied from 1000–3000, and heat flux at the bottom of FMCHS is 50 W/cm2. The results show that with the increase in Re, wall temperature significantly reduced. With the addition of nanoparticles to the base fluid, heat transfer increased; however, there is increase in pressure drop. Nu increased almost 4 times at Re = 3000 with the addition of nanoparticles. Performance evaluation criterion (PEC) was calculated to know the actual performance of the FMCHS. It is found that PEC is increased significantly with nanofluid. Overall employing nanofluid is found to be beneficial in this current study of FMCHS.