| 摘要 |
PURPOSE:To increase safety in such a way that two partial injection zones respectively take the turbine center as their center to keep their symmetrical positions, and excitation force of a turbine rotor blade due to the partial injection of working fluid is reduced, or excitation degree is staggered. CONSTITUTION:Injection zone 1 in a double-arc turbine stator blade is a partial circumferential zone which is got in between diameters 6 and 7 which have been obtained by turning the reference diameter 5 counterclockwise by angles -alpha and -beta. On another hand, injection zone 3 is a partial circumferential zone which is got in between the diameters 7 and 6 which have been obtained by turning the reference surface 5 clockwise by angles alpha and beta. In other words, the injection zones 1, 3 are in the symmetrical positions taking the turbine center M as their center. Then, when the turbine is at its full load, fluid is injected through the stator blades which are arranged over the total circumferential zone, and when the turbine is at its partial load, the fluid is injected through stator blades which are arranged at the injection zones 1, 3. |
