Aerodynamic and heat transfer performance of double-jet film cooling using internal crossflow supply configuration

The double-jet film-cooling structure is recognized as an effective method for cooling the hot-section parts of turbines. Recent studies highlight the significant impact of internal supply configurations on the aerodynamic and thermal characteristics of external film cooling. Therefore, this study investigates the aerodynamic and heat transfer performance of double-jet film-cooling holes under crossflow conditions, both with and without ribs, through numerical simulation. The study examines both positive and negative crossflow supply directions across four blowing ratios (ranging from M = 0.5 to 2.0), using a cavity supply case as the baseline for comparison. By modifying the geometric and aerodynamic boundary conditions, the focus is on analyzing the changes in the flow field structure, aerodynamic losses, and cooling performance across various supply configurations. The results reveal that at low blowing ratios, double-jet film-cooling holes are significantly affected by crossflow. Compared to the cavity supply case, the discharge coefficient in the crossflow cases decreases by up to 45.1 %. Different internal crossflow supply configurations exhibit distinct optimal blowing ratios, with the smooth crossflow supply configurations beginning to demonstrate advantages in cooling performance when M ≥ 2.0. This research emphasizes the importance of a rational configuration of the cooling structure—including the internal structure, supply direction, and hole parameters—for substantially enhancing film cooling performance under high blowing ratios (M ≥ 1.5). The findings deliver actionable design principles and performance optimization guidelines for double-jet film cooling configurations.