Numerical simulation of topology optimization in transpiration cooling incorporating non-uniform permeability

The utilization of transpiration cooling exhibits immense potential in the realm of active thermal protection. The present study focuses on optimizing the cross-sectional structure of a porous medium plate using the variable density method topology optimization, with the objective of minimizing average temperature on heated wall, and a topology-optimized porous plate structure is obtained. The results indicate that, in comparison with the traditional uniform porous plate, the optimized porous plate not only enhances convective heat transfer between coolant and solid skeleton but also increases outlet velocity of coolant and improves its ability to push away from high-temperature air, thereby enhancing overall transpiration cooling efficiency. Moreover, the topologyoptimized plate exhibits robust cooling capacity under varying coolant flow rates and mainstream temperatures. Specifically, at starting location of transpiration, the optimized plate achieves up to a 27% increase in cooling efficiency compared to uniform porous plate. However, it also requires higher coolant supply pressure with an inlet driving pressure that is 4% greater than that of uniform porous plate. The research presented in this paper offers valuable insights for enhancing the thermal protection performance of transpiration cooling.