Performance analysis and parameter optimization of microchannel heat sink with porous-solid composite ribs

To address heat dissipation in high-integration electronic devices, this study proposes a novel microchannel design featuring porous-solid composite ribs. Numerical simulations are conducted to analyze heat transfer and flow characteristics of the microchannel. We define four structural parameters: the length and width ratios of porous-solid composite ribs ( α , β ) and polygonal ribs ( η , γ ), and investigate the influence on the Nusselt number ( Nu ) and the friction factor ( f ). The optimization process employs artificial neural network models and non-dominated sorting genetic algorithm to determine the optimal solution. Results indicate that the application of the porous medium increases the effective heat transfer area and optimizes the pressure distribution compared with the solid rib microchannel. Parameters α and β exert a more significant influence on heat transfer and pressure drop, while η and γ primarily affect the flow characteristics of the working fluid. Optimal solution is achieved at Nu = 86.87 and f = 2.71, representing a 6.28% increase in Nu and a 29.43% reduction in f relative to the primary design, along with the highest performance enhancement coefficient (PEC) value among three optimal designs under Re = 300 and 520.