Numerical study of film cooling from converging slot-hole on a gas turbine blade suction side

A numerical research on the film cooling performance of a single row of converging slot-holes (console) on the blade suction side in an engine-simulated environment was carried out, in which the Reynolds number was arranged from 400,000 to 600,000 and the blowing ratio was arranged from 0.5 to 3. A comparison in contrast to a cylindrical hole was made and the effects of major factors on the film cooling effectiveness and aerodynamic loss were explored, including the film hole location, blowing ratio and primary flow Reynolds number. For the console cooling geometry, the interaction between the coolant jet from inclined console and the mainstream flow results in secondary vortices with a sense of rotation opposite to the kidney pair, which makes the coolant jet from the console be of the flow mechanism for suppressing normal penetration. Additional corner vortices are also observed in the intersection of two consoles on the convex surface. When the film holes are located upstream of the channel throat, the level of aerodynamic loss for the console is obviously less than the cylindrical holes. At higher blowing ratios, more coolant jet momentum is transferred to the tangent and lateral flow of the coolant jet issued from the consoles, resulting in a film cooling enhancement. The console row shows great potential in the blade film cooling application, especially favorable when it is located upstream of the channel throat.