| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an axial-flow hydraulic turbine and a discharge ring thereof which reduce the velocity of the flow at an outlet of a draft tube as much as possible, and achieve enhancement of the energy efficiency. <P>SOLUTION: This discharge ring of the axial-flow hydraulic turbine according to one embodiment, is a discharge ring which covers a runner. The runner includes: a runner hub which can rotate around a first axis; and a runner vane which is disposed in a periphery of this runner hub. The runner vane can rotate with respect to this runner hub around a second axis different from this first axis, and has a spherical peripheral face. The discharge ring has: a spherical part which is disposed opposing to the peripheral face, and has a spherical inside face; and a throat part which has a first inside face disposed on the upstream side, and forms a first circular arc on a face including the first axis, and a second inside face disposed on the downstream side, and forms a second circular arc of a radius smaller than that of the first circular arc on the face, and connects the spherical part with the draft tube. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
