摘要 |
The invention relates to the design of a fixed-blade assembly in an axial flow steam turbine and is based on the recognition that the design of the interfacing region (fillets) between the radial ends of the blades and the end-blocks to which they are attached or of which they form a part has a significant effect on stage efficiency. The invention recognizes an optimum fillet radius in the range 0.15-0.3 of the throat dimension between the trailing edge of one blade and the suction surface of an adjacent blade, and more particularly 0.20-0.50. The fillet configuration is advantageously applied to a turbine having blades which are of constant cross-section, are curved in the radial (height) direction and are convex from root to tip on its pressure face, the result being a considerable gain in stage efficiency.
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