Computational Fluid Dynamics Analysis of Enhanced Heat Transfer in Microchannel Heat Sinks with Novel Fin Geometries for High-Power Electronics Cooling

Thermal management has become a critical bottleneck limiting the performance, reliability, and miniaturization of advanced high-power microelectronic devices. In this study, a three-dimensional computational fluid dynamics (CFD) investigation is conducted to examine the conjugate heat transfer and hydrodynamic characteristics of microchannel heat sinks (MCHS) utilizing novel secondary fin geometries. Five distinct microchannel configurations—conventional straight rectangular channels, interrupted rectangular fins, hydrofoil-shaped pin fins, staggered chevron fins, and an innovative hybrid bifurcated-aerofoil fin design—are numerically evaluated using deionized water across Reynolds numbers ranging from 150 to 900 under a uniform base heat flux of 1.5 MW/m². The governing continuity, Navier-Stokes, and energy equations are resolved using a validated finite-volume framework accounting for temperature-dependent thermophysical properties. The results demonstrate that the hybrid bifurcated-aerofoil geometry significantly disrupts thermal boundary layer development while inducing controlled longitudinal vortex generation, leading to an average enhancement of 48.6% in the Nusselt number relative to conventional straight channels. Although frictional pressure drops increase concurrently, the overall thermal-hydraulic performance evaluation criterion reaches 1.34 at a Reynolds number of 600, mitigating peak substrate temperatures to well within acceptable semiconductor operational thresholds. These findings offer critical design guidelines for developing next-generation, high-efficiency liquid-cooling systems for concentrated heat flux electronic applications.