Thermal Performance Optimization of Perforated Fins for Flat Plate Heat Sinks Using CFD Approach

Abstract

A comprehensive multi-dimensional computational fluid dynamics (CFD) analysis was conducted on a flat plate heat sink, equipped with four perforated fins. This study aimed to optimize the thermal performance by exploring the effects of the geometry and placement of the perforations within the fins. The heat transfer was modelled under conduction for the heat sink body, and natural convection for the enclosure. The investigation focused on the combined influence of the shape of the fin perforations (circular, square, triangular) and their spatial positioning (bottom, middle, top) on the overall thermal performance. It was observed that the temperature gradients (ΔT) from the bottom to the top of the fins were significantly enhanced with the introduction of perforations. Notably, the smallest ΔT of 2.64℃ was recorded with circular perforations, independent of their placement within the fin matrix. Conversely, the highest ΔT of 12.58℃ was observed when the perforations were triangular in shape. Furthermore, an increase in ΔT was noted when all perforation matrices were relocated from the top to the bottom of the fins. Interestingly, the heat transfer coefficient was found to be higher when the heat sink made use of perforated fins. However, the effect of the perforations' shape and placement on this coefficient was found to be less significant. In conclusion, optimal thermal performance was achieved with circularly perforated fins. The buoyancy effect within the enclosure and in the vicinity of the fins was amplified when the heat sink's fins were top-positioned and circularly perforated. This resulted in a 15.6% increase in ΔT, but also a 29.6% increase in the heat transfer coefficient, indicating an overall enhancement in thermal performance under most tested conditions.

Design and Performance Analysis of a Composite Thermal Protection Structure for a Robot Pan–Tilt

“…In high-temperature environments, external heat is transferred to the skin of the structure through convective heat transfer. The heat flux density conv q of convective heat transfer is determined in the following [37]:…”