A novel manifold microchannel heat sink with thermal-responsive deformable fins for adaptive cooling

Random hotspots pose a critical threat to the thermal safety of high-flux electronic devices. The existing solutions of adaptive cooling face limitations in both regulation precision and design predictability. To address the issues, this study proposes a novel manifold microchannel (MMC) heat sink integrated with thermal-responsive deformable fin (TRDF). It leverages the inherently discrete unit of MMC heat sink to enable pixel-level cooling adjustment at targeted hotspots. The sinusoidal TRDF, constructed from a shape memory alloy (SMA) beam and elastic wrapping, is proposed for temperature-responsive deformation. When the original length of SMA beam varies, the span and height of TRDF changes differently upon heating. Thus, the thermal-hydraulic profile (THP) of unit is established, characterizing the coupled effects of inlet velocity and TRDF geometry on heat transfer coefficient and flow resistance. This THP-based methodology, combined with the flow distribution model of MMC heat sink, can identify effective deformation paths that yield significant heat dissipation adaptivity to hotspots. The results show that the horizontal configuration of TRDF can achieve stable adaptive performance, increasing the effective heat transfer coefficient by up to 14.4% under hotspot conditions. Its heat transfer coefficient also exceeds 32,700 W/m²·K. Altogether, the novel design and methodology establish a rational framework for developing predictable adaptive cooling systems of high performance.