Numerical Simulation Of Pressure Drop Across Micro-Pin-Fin Arrays

Abstract

Liquid-cooled micro-pin-fin heat sink thermal design and performance assessment requires an accurate understanding and prediction of pressure drop and heat transfer associated with liquid single-phase flow in micro-pin-fin arrays. This study investigated water flow pressure drop across micro-pin-fin arrays with different geometries using numerical simulations implemented with COMSOL Multiphysics software. COMSOL simulations were modeled after an existing experimental set up (180 μm in diameter, 683 μm in height, and 399 μm in both longitudinal and transverse pitches) and previously studied numerical analyses (various height to diameter ratios) were performed. COMSOL results were compared to experimental and numerical results. Lower mean absolute error (MAE) values showed good agreement and validated the COMSOL simulations. Once validated, 2D and 3D numerical simulation of various micro-pin-fin array geometries were conducted over seven Re numbers (20, 50, 100, 215, 410, 605, 800). Various changes to transverse pin separation (Wsp), longitudinal pin separation (Lsp), and diameter were modeled and simulated. The results showed that an increase Wsp decreased friction factor and vice versa. Changes to Lsp had little effect on friction factor. Lastly, an increase in pin diameter increased friction factor. These results provide a better understanding of flow resistance and its relationship to the geometrical parameters.