Pseudo-three-dimensional turbulent topology optimization research for regenerative cooling channels incorporating thermal property variations and adaptive convective heat transfer coefficient

Scramjet operation at high Mach numbers intensifies thermal protection requirements, demanding optimized regenerative cooling channels to ensure engine safety through improved cooling efficiency. Although topology optimization methods have been extensively applied to cooling channel design, existing approaches cannot be directly adapted to regenerative cooling channels characterized by complex flow and heat transfer mechanisms. Accordingly, this study develops a pseudo-three-dimensional topology optimization framework for regenerative cooling channels that incorporates hydrocarbon fuel thermal property variations and turbulent flow effects. To address the heat transfer characteristics of supercritical hydrocarbon fuels, an adaptive convective heat transfer coefficient model is formulated to capture the thermofluidic dynamics under these conditions. The investigation prioritizes two key aspects: the influence of thermal property variations and the effect of thermos-fluidic design layer thickness on optimization outcomes. The thermal and flow performance of the topology-optimized channel is further analyzed using a three-dimensional flow and heat transfer model under supercritical pressure conditions. Comparative analysis demonstrates a 9.8% reduction in maximum heated surface temperature relative to conventional designs, along with improved overall thermal performance. The experimental results conclusively demonstrate that the topology-optimized channel exhibits enhanced thermal performance compared to conventional designs. The proposed methodology provides an effective approach for optimizing scramjet regenerative cooling system designs.