Experimental investigation of double-wall cooling with lattice structures for gas turbine blades

This study proposes and investigates a double‐wall cooling configuration incorporating cube and tetra lattice structures. Test specimens were fabricated to match the Biot number of actual gas turbine conditions. The overall cooling effectiveness was experimentally measured under various blowing ratios (0.4, 0.6, and 0.8) using infrared thermography. In comparison to a conventional double‐wall design and double‐wall systems with pin‐fins, the lattice structure configurations exhibited superior cooling performance, achieving a maximum area‐averaged improvement of 6.45% relative to the conventional baseline at a blowing ratio of 0.6. Complementary numerical simulations were performed to explain the internal flow behavior. The results indicate that the lattice structure enhances convective heat transfer by inducing multiple impingement and reattachment flows, while also facilitating improved conduction through the interconnected structure. Furthermore, to verify the additive manufacturability, a blade with a lattice structure was fabricated via selective laser melting (SLM) using CM247LC, where computed tomography (CT) was used to inspect the internal lattice structure. Consequently, the self‐supporting lattice structure demonstrates strong potential for advanced thermal management of turbine components, offering both enhanced heat transfer capability and reduced manufacturing constraints associated with overhangs in additive manufacturing.