| 摘要 |
PURPOSE: To reduce seal gap and friction loss and to increase turbine efficiency by forming a means such as a diagonal gap at an inlet throttle location while arranging a plurality of throttle locations in a cover plate of a rotation blade opposite to the casing. CONSTITUTION: The device is for sealing a gap between a casing 2 configured with a conical profile of an axial-flow turbomachine and rotation blade 6c installed in the rotor. The rotation blade 6c plays sealing function to the casing 2 while defining a plurality of radial gaps 16, 17 by plural serrations 12 to 14 formed in an annular cover plate 11. In this case, the rotation blade 6c seals against the casing 2 at the inlet and outlet ends of the conical ends. The cover plate 11 has three throttle locations with respect to the casing 2, and the inlet end throttle 19 forms a diagonal gap. By this constitution, reduction of seal gap and friction loss and improvement of turbine efficiency are realized. |
