13th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Heat Transfer & Cooling
Shaped holes are considered as an effective solution to enhance gas turbine film-coolingperformance, as they allow to increase the coolant mass-flux, while limiting the detrimen-tal lift-off phenomena. A great amount of work has been carried out in past years onbasic flat plate configurations while a reduced number of experimental works deals witha quantitative assessment of the influence of curvature and vane pressure gradient.In the present work PSP (Pressure Sensitive Paint) technique is used to detail the adiabaticeffectiveness generated by axial shaped holes with high value of Area Ratio close to 7, inthree different configurations with the same 1:1 scale: first of all, a flat plate configura-tion is examined; after that, the film-cooled pressure and suction sides of a turbine vanemodel are investigated. Tests were performed varying the blowing ratio and imposing adensity ratio of 2.5. The experimental results are finally compared to the predictions oftwo different correlations, developed for flat plate configurations.