Turbine blade

摘要

The invention relates to the design of (particularly) a fixed blade in an axial flow steam turbine. A conventional blade is of prismatic form with an aerofoil cross-section and extends radially between annular end blocks. The inventive blade is curved in the radial (height) direction, being convex from root to tip on its pressure face. The setting angle relative to the corresponding prismatic blade is therefore fine at the root and tip and coarse at the blade mid-height. The throat opening is thus reduced at root and tip and increased at mid-height so displacing some mass flow away from both lossy end wall regions. A considerable gain in the stage efficiency results. A further improvement results from providing an optimum corner fillet between the blades and end walls at the root and tip.