Geometrie einer Turbomaschinenschaufel

摘要

The steam turbine comprises a stationary cylinder for containing a steam flow, and a rotor enclosed by the cylinder; and a row of blades, each having a root portion attached to the rotor and an airfoil portion. Each of the airfoil portions has a base portion and a tip portion defining an airfoil height; and a rounded leading edge portion and a trailing edge. A pressure surface and a generally concave suction surface extend between the rounded leading edge portion and the trailing edge and define a thickness of the airfoil. The pressure surface over a first portion of the airfoil height has a curvature undergoing an inflection at a location, disposed within the pressure surface. A first portion of the pressure surface extends over the first portion of the said airfoil height has a concave curvature and is disposed between the inflection location and the rounded leading edge portion. A second portion of the pressure surface extending over the first portion of the airfoil height has a convex curvature and is disposed between the inflection location and the trailing edge. The concave curvature of the first portion of the pressure surface has a maximum negative value in excess of -0.03mm x power -1, the convex curvature in the portion of the pressure surface having a maximum positive value in excess of +0.03 mm x power -1.