Optimization and thermal-hydraulic performance investigation of hierarchical-tapered manifold microchannel cold plate for chip cooling

Manifold microchannel, as an emerging cooling solution, is of great significance for advancing chip thermal-management technologies. To further improve the comprehensive performance of manifold-microchannel structures, this paper proposes a hierarchical tapered manifold microchannel (HTMMC) liquid-cooling plate for server-chip heat dissipation. The performance advantages of the HTMMC cooling plate are demonstrated by both experimental tests and numerical simulations. Using the validated numerical model, a sequential framework consisting of single-factor experiments, Plackett-Burman screening experiments and Box-Behnken response-surface methodology is adopted to investigate multi-parameter interaction effects and seek the HTMMC configuration with optimal comprehensive performance. The surrogate-model-predicted optimum structural parameters are as follows: manifold hierarchical length ratio of 1, manifold inlet-to-outlet area ratio of 1/2, microchannel width of 0.268 mm, microchannel height of 3.73 mm, and manifold height of 5.70 mm. Under these optimum parameters, the absolute PEC value of HTMMC is 1.383, and the deviation between surrogate-model prediction and CFD simulation is only 0.4%. For experimental comparison, a conventional traditional microchannel (TMC) liquid-cooling plate representing mainstream chip-cooling schemes is fabricated and tested alongside the initial HTMMC and optimized HTMMC prototypes. Experimental results reveal that the optimized HTMMC achieves better flow and heat-transfer performance than both the TMC and initial HTMMC. The PEC ratio of the optimized HTMMC is 1.203–1.401 relative to the initial HTMMC prototype and 1.678–1.849 relative to the TMC prototype.