Flat Plate Film Cooling At The Coolant Supply Into Triangular And Cylindrical Craters

The results are given of the film cooling numerical simulation of three different schemes including single-array of the traditional round inclined holes, as well as inclined holes arranged in the cylindrical or triangular dimples (craters). The results of simulation showed that at the medium and high values of the blowing ratio (m > 1.0) the scheme with coolant supply into triangular craters improves the adiabatic film cooling efficiency by 1.5...2.7 times compared to the traditional array of inclined holes, or by 1.3...1.8 times compared to the scheme with coolant supply into cylindrical craters. The greater film cooling efficiency with the coolant supply into triangular craters is explained by decrease in the intensity of secondary vortex structures ("kidney" vortex). This is due to the partial destruction and transformation of the coolant jets structure interacting with front wall of the crater. Simultaneously, the film cooling uniformity is increased in the span-wise direction.