In supersonic combustion ramjet (SCRamjet), regenerative cooling channels face challenges from high heat flux and strict fuel quantity constraints. Moreover, the thermal boundary conditions of cooling channels are typically non-uniform, which may induce non-uniform fuel distribution. This can lead to serious waste of fuel cooling capability and even cause over-temperature conditions. To ensure heated wall safety, topological optimization of regenerative cooling channels is urgently needed to improve reasonable flow distribution and efficient utilization of cooling capacity. In this work, a three-layer pseudo-three-dimensional (pseudo-3D) model is developed and validated, accounting for turbulent flow and thermal property variations of hydrocarbon fuel. Topological optimization is further conducted on regenerative cooling channels under uniform and multiple non-uniform heat flux distributions. The three-dimensional (3D) numerical results of topology-optimized channels demonstrate that discrete ribs promote fluid divergence and convergence, enhancing heat transfer and optimizing flow distribution. The maximum wall temperature is reduced by 9.3%, 8.5%, and 13.17%, respectively. The Nusselt number is increased by 42.5%, 41.4%, and 49.3%, respectively. Finally, cylindrical pin-fins are used as basic structural units to construct the topological structure, avoiding unreasonable designs from the topology optimization process. This approach achieves a 6.9% reduction in maximum wall temperature. The research in this paper is expected to further support the optimized design of regenerative cooling channels.
Qi et al. (Fri,) studied this question.