Study of film cooling on a turbine guide vane pressure side with a serrated trench

This study presents an investigation into the film cooling characteristics of a novel serrated trenched-hole structure on the pressure side of an enlarged turbine guide vane. Experimental measurements and large-eddy simulations (LES) are employed with the conventional straight trenched hole and a row of conventional cylindrical holes adopted for comparison. LES with the Smagorinsky-Lilly model is validated by the experimental measurement and is selected for all numerical cases. The results demonstrate the pronounced advantage of enhancing film cooling performance of the serrated trench, especially at higher blowing ratios. Noticeable distinctions of vortex structures between the serrated trench and the conventional straight trench are detected. Consequently, the serrated trench facilitates improved attachment and lateral spreading of the coolant jet and outperforms the straight trench in terms of film cooling effectiveness. Through experimental and numerical analyses, this study explores the potential of the trenched-hole structure to enhance cooling effectiveness and provides valuable insights and contributions to the advancement of turbine blade design.