Application of a dual manifold topology-optimized pin fin cold plate for high heat flux thermal management of automotive power inverters

This study puts forward a new dual manifold topology-optimized pin fin cold plate to address the high heat flux thermal management of power conversion units in electric and hybrid vehicles. The optimized pin fin cold plate was experimentally investigated using six thick-film heaters, enabling heat fluxes up to 200 W/cm², with deionized water as the coolant, while temperature measurement and monitoring were performed using six high-accuracy Class A PT100 resistance temperature detectors. The numerical simulations were carried out for circular, elliptical, airfoiled (0-degree attack angle), and funnel pin fin shapes to enable systematic performance comparison. With a peak heat transfer coefficient of 18 kW/m²·℃, the optimized pin fin outperformed its counterparts, delivering a 47–66% enhancement in heat transfer, up to 19% lower thermal resistance relative to baseline fins, and a 15% reduction in pressure drop. Its thermal resistance ranges from 0.0249 to 0.0271 ℃/W, and pressure drop remains between 3 and 6.5 kPa. Topology‑optimized pin fins keep temperatures within the safe range, achieving 3.95% temperature uniformity, which is 54% better than the baseline. Compared to the baseline pin fin, the proposed new pin fin decreases the average module temperature by 12–14.5℃ and halves the end-to-end temperature variation. The improvements are mainly attributed to enhanced flow distribution and intensified boundary-layer disruption achieved by the spatially differentiated pin fin structure. Overall, the proposed topology-optimized cold plate exhibits nearly double the energy efficiency of the baseline pin fin design, as confirmed by figure of merit and performance evaluation criterion analyses, demonstrating its strong potential for advanced thermal management of high-power automotive electronics.