Numerical investigation on heat transfer characteristics of internal cooling channels with perforated pin-fins in gas turbine blade

In aeronautical jet engines, internal cooling is commonly employed to keep the blade surface temperature below the material's thermal limit to ensure the structural integrity and performance of turbine blades. This study aims to evaluate the heat transfer characteristics of internal cooling channel in gas turbine blades with perforated pin-fins compared to regular pin-fins (without perforated pin-fins) configurations using the Reynolds averaged Navier–Stokes equations with the k–ω turbulence model. The numerical results demonstrated that perforated pin-fins configurations increase the averaged Nusselt numbers (Nu¯) and heat transfer efficiency index = η and reduce friction factor (f) compared to the regular pin-fins. The cooling flow through the perforated pin-fins creates the jet-like flow, breaking the wake vortices behind the pin-fins near the heated endwalls surface and creating a high heat transfer zone. With the Reynolds numbers from 14 000 to 36 000, the numerical results of the perforated pin-fins (reference case) show an increase in Nu¯ and η by 61.28%–69.89% and 69.97%–80.19%, respectively, while f decreased by 14.56%–16.18% compared to the regular pin-fins. With perforated expansion at Re = 21,500, the heat transfer performance could be improved by up to 77.18% and the friction factor (f) was considerably reduced as low as 19.42% at WP/D = 0.8. This study provides valuable insights into the potential improvements in thermal performance achievable through perforated pin-fin configurations in gas turbine blade cooling channels.