An Experimental Investigation of the Effects of Massive Film Cooling on the Aerodynamics of a Turbine Airfoil

: The effects of massive film cooling through multiple rows of discrete holes on the aerodynamics of a typical two-dimensional turbine airfoil have been studied experimentally using a single blade positioned in a contoured channel. The channel walls, shaped to simulate the presence of adjacent airfoils in a cascade, were both porous and movable to allow adjustment of the flow direction and airfoil surface pressure. Electrically heated air was used as the primary flow, while room temperature coolant air was emitted from five rows of discrete holes on each airfoil surface to film cool the regions aft of mid-chord. Hole geometries angled in the spanwise, chordwise, and vertical directions were employed to achieve coolant-to-inlet mass rate ratios as high as 0.05 for blowing from the single blade.