Rectangular and Square Cross-Sections Microchannel Heat Sink CFD Simulation and Analytical Validation Using Liquid Water & Water-Aluminium Oxide Nanofluid as a Cooling Medium

Abstract

In this study, cooling performance of copper material based microchannel heat sink was investigated using two different approaches which are CFD and Analytical. Microchannel heat sink with two different cross-sectional geometries of rectangular and square was considered for the present study. In the present work CFD simulation is carried out using two different cooling fluids which are liquid water and water-Al2O3 nanofluid. Nanofluid volume fraction of 0.3% was used for present study. Re number in between 200-1000 was used for the present study. For CFD simulation purpose heat sink of dimension of 25.4mm × 25.4mm × 2.384mm is considered in the study. Boundary condition of constant heat flux is assumed by providing heat flux at constant rate at bottom of the assembly. To compare between square and rectangular cross section microchannel heat sink, the hydraulic diameter is kept same in both the cases and CFD simulation was conducted. With using water-Al2O3 nanofluid as the working fluid the rectangular cross section is showing better performance in terms of cooling as compare to the square cross section. Drop in pressure results in rectangular section calculated using water Al2O3 nanofluid using both CFD and Analytical approach are in good agreement with difference of 13.4%