Multidimensional spatial optimization and thermo-hydraulic analysis of pin-fin liquid-cooling channels

Pin-fin liquid cold plates used in high-power motor controllers often encounter excessive pressure drops, poor temperature uniformity, and insufficient heat dissipation capacity, which severely limit the operational efficiency and service life of the controllers. To address these challenges, this study proposes a sub-regional, multi-objective optimization design framework characterized by the synergy of multi-spatial parameters. Targeting discrete heat source modules, the framework improves temperature uniformity and optimizes thermo-hydraulic performance through regional partitioning and the coupled optimization of spatial parameters. Prior to optimization, a systematic analysis of the optimal coupling ranges between various spatial characteristic parameters was conducted to define the optimization design space. The results indicate that when the spanwise pin-fin spacing exceeds the streamwise spacing, all optimized configurations consistently outperform the comparison configurations in terms of overall performance, with the performance gap becoming more pronounced as the porosity decreases. The in-line pin-fin arrangement with a positive inclination angle of θ = 112.5° achieved dual optimization benefits, enhancing heat transfer and reducing pressure drop. As the inclination angle increases, flow resistance continuously decreases while maintaining favorable heat transfer performance. After region-based optimization based on representative heat-source modules, the optimized liquid-cooling plate reduced the maximum temperature (T_max), maximum temperature difference (ΔT_max), and pressure drop (ΔP) by 4.8 °C (4.2%), 8.6 °C (90.2%), and 361 Pa (6%), respectively, significantly improving thermal management efficiency.