Cooling High Power Microchip Using Metallic Porous Heat Sink

Modern living and technological advancements demand high-power microchips, leading to an increase in chip surface temperatures. To mitigate this heat, porous metallic heat sinks are employed. This study presents a simulation of a high-power microprocessor (>10⁴ W/m²) encased in a porous metallic heat sink. The microchip measures 4 cm in diameter with a thickness of 5 mm. The governing equations are solved numerically using the finite element method, implemented in COMSOL Multiphysics software. This paper investigates the cooling performance of a microchip through natural convection, focusing on three key parameters: aspect ratio, porosity, and heat sink material. The study considers heat sink porosities of 0.2, 0.4, and 0.8; aspect ratios of 0.2, 0.5, 1, and 2; and heat sink materials including copper, aluminium, and steel. Results are presented as temperature and Nusselt number contours on the microchip's surface. The findings indicate that copper achieves the lowest surface temperature (41.58℃) and the highest Nusselt number (243.81) at an aspect ratio of 2. Increasing the aspect ratio enhances the heat transfer rate and, consequently, the Nusselt number. Conversely, steel exhibits the highest surface temperature (89.35℃), the lowest heat transfer coefficient (164.89 W/m·K), and the lowest Nusselt number (62.84).