高水头岸边式溢洪道泄槽段水力特性研究

Study on the Hydraulic Characteristics of Chute Section of High-head Bank Spillway

为了保证高水头溢洪道上泄槽段的水流平顺进入下泄槽段以及下泄槽段减免空蚀破坏,同时提高渥奇曲线段底部的水流空化数和避免负压;在变坡处采用了渥奇曲线和下切直线段相结合,其后接掺气坎的形式。针对下泄槽陡坡段容易出现水翅现象,提出了在两侧墙增设一段与泄槽底板成一定夹角的消翅悬梁,从而有效地抑制了水翅的发展,稳定了泄槽流态,且悬梁发生空蚀破坏的可能较小。该体形布置形式对类似工程有一定的参考价值。

In order to guarantee the .water body of upper chute section transited to lower chute section smoothly, to reduce the cavitation of lower chute section, and to increase the cavitation number of water body and avoiding negative pressure on the variation-grade section ogee section, we adopt the combination of Ogee curve with down-tangency straight-line section in the gradient-changed section. An aerator type was set up behind the variation-grade section. Because lower chute section is apt to present water-wing, one section suspension girder was set up on the side of lower chute walls. The girder and chute base-plate became certain contained angles ,which suppresses the development of water-wing effectively and let out the flow sate steadily. Meanwhile the possibility was relatively little that the suspension girder destroyed by cavitation. Such layout type could be used for reference in the design of similar projects.