Numerical modeling of microchannel heat sink performance covered by a corrugated porous layer containing phase change slurry assuming local thermal non-equilibrium

In this study, performance of a microchannel heat sink (MCHS) containing a suspension of phase-change materials and water is investigated, numerically. A porous layer consisting a perfect conductive solid matrix was attached into the walls of the MCHs. Due to the high solid matrix to coolant fluid conductivity ratio, the Local Thermal Non-Equilibrium (LTNE) approach is utilized in the porous domain. The governing equations were solved using the finite element method (FEM). Effect of design parameters, such as different geometric configurations for solid/porous walls, porous layer thickness, stepwise porosity arrangements, porous wall wavelength, slurry fusion temperature, and etc., were evaluated for pressure drop, heat transfer and Performance evaluation factor (PEF). Based on the results, thickness of the porous wall influences PEF significantly. Specifically, at an inlet velocity of 2.5 m/s, the performance evaluation factor increases by 17.39% for a thickness of 0.1 mm compared to 0.2 mm. The optimal hydro-thermal performance of MCHS is obtained for the corrugated microchannel wall with straight porous layer configuration. According to the results, the LTNE effects augment sharply in the entrance region of the MCHS and diminish through the channel outlet.