| 摘要 |
PURPOSE:To check any increase in a tangential velocity component in a runner outlet for a regular flow as well as improve a degree of turbine efficiency, by installing a belt plate in a sense of intercepting a flow of water cylindrically in a position proximate to an outlet of the flow passing through a clearance between the outer circumference of a runner band and the inner circumference of a runner chamber. CONSTITUTION:A cylindrical belt plate 6 is installed in an outlet of a flow passing through a clearance 5 between the outer circumference of a runner band 3 and the inner circumference of a runner chamber 4 so as to intercept the flow. This belt plate 6 is attached to an inner wall of a draft tube 7 with a proper clearance kept up. With this constitution, a flow passing through the clearance 5 is led into the same direction as a regular flow passing through the side of a runner 1, whereby the flow running past the clearance 5 is prevented from colliding with the regular flow at an outlet of the runner 1. Therefore, any increase in a tangential velocity component in the outlet of the runner 1 of the regular flow is preventable, thus turbine efficiency is well improvable. |
