Abstract: A turbine blade assembly composed of a rotor which is rotatable about a turbine axis of rotation and a plurality of turbine blades supported by the rotor, each blade having a root and the rotor being provided with a groove shaped for holding each root in a manner such that the root and groove have mutually contacting surfaces which apply a radially inwardly directed restraining force to the root, the root further having a bottom facing the turbine axis and the groove having a base which is located radially inwardly of, and faces, the root bottom. The mutually contacting surfaces of the root and the groove are pressed together by means of at least one disc spring compressed between the root bottom and the groove base.

Abstract: Methods and apparatus for determining a profile of cross-sectional areas of a turbine blade. The cross-sectional area between two selected points along the length of the blade is determined by calculating the changes in the buoyant force exerted upon the blade as the blade is immersed into a volume of water contained in a tank.