Numerical and Experimental Studies on Pressure Drop in Milling Parameter Optimized Aluminium Heat Sink Channel

Abstract

Micro-/mini-channel heat sink is an effective scheme for cooling electronic components. The main advantages of such a heat sink are robust design, compactness and high surface-to-volume ratio. Present study investigates effect of channel surface roughness on its pressure drop using numerical and experimental techniques. Numerical analysis was conducted using commercial computational fluid dynamics analysis software, ANSYS Fluent, and results for velocity and pressure characteristics were obtained. The channel surface conditions were changed as smooth channel and rough channels with ε = 2.5 μm and ε = 3.85 μm. In experiments, a 20-mm-long square channel of depth 2 mm was fabricated in aluminium substrate using milling parameters optimized to achieve the best surface finish. The water flow conditions across the channel were changed from Re = 200 to Re = 1000. Results show that the pressure drop values ranged from 20 to 170 Pa and the average pressure drop measured in micro-milled channel is close to rough channels with ε = 2.5 μm.