The bifurcated microchannel heat sinks (MCHS) have garnered significant attention owing to their advantages of a large heat transfer area, compact design, and reduced operating costs. And the gradient porous material (GPM) has been widely applied in enhanced heat transfer applications due to its flexibly designable structure, higher thermal conductivity and better stability. Therefore, a three-dimensional numerical model for bifurcated MCHS with gradient porous walls is established, in order to improve the thermal performance. Six porosity gradient configurations with the same pore size and average porosity are proposed. The effects of porosity arrangement, different inlet velocity and porosity gradient difference on the flow and heat transfer properties of MCHS were numerically analyzed. The results indicated that the design with small porosity near the bottom wall and large porosity near the top of the bifurcated MCHS contributes to enhancing the overall performance. Where, the Nusselt number of 3SIP is the largest, which increases by 12.4% compared with the UP. A comprehensive performance evaluation factor (PEF) was introduced to analyze the thermal and hydraulic performance of bifurcated MCHS, where the 2SIP has the best comprehensive performance and the PEF factor increases by 15.9% compared with the UP. The results of this study improve the heat transfer performance of MCHS, and promote the application of gradient porous materials and other enhanced heat transfer means for composite heat transfer.

Xinyu Shi, Wanting Hu, Chenhao Li, Jianing Jiang. Numerical Study on Flow and Heat Transfer in Bionic Bifurcated Microchannels with Gradient Porous Wall. Academic Journal of Materials & Chemistry (2025), Vol. 6, Issue 2: 63-72. https://doi.org/10.25236/AJMC.2025.060209.

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