泄洪洞掺气减蚀设施空腔回水研究

Measures to Relieve the Backwater of Aeration Structure of Spillway Tunnel

泄洪洞内高速水流空化引起过流表面空蚀一直以来都是一个值得关注的问题,掺气减蚀是解决泄洪洞过流表面空蚀的有效措施。以某水电站泄洪洞明流泄槽的掺气设施为例,从对掺气坎体型增加坎高、加设坎下平台、加设下游陡坡、圆弧形底板等多个角度进行了探索比较优化。研究成果表明:挑跌坎掺气槽后接圆弧底板布置形式,较好地解决了掺气坎下游水流反向漩滚和空腔回水的问题。这一成果为类似掺气设施的布置提供了参考。

Aeration is an efficient measure to mitigate the cavitation of flow surface in spillway tunnel causeo Dy mgn speed flow. With the aeration structure of the free flow chute of a hydropower station spillway as an example, we optimized the aerator by raising the height, connecting a lower fiat segment, steep slope or arched bottom in the downstream of aerator, and compared the effects of these schemes. Results showed that the aerator slot connected by arched bottom could solve the problem of counterclockwise vortex and cavity backflow in the downstream of aera- tor. The research result could serve as a reference for the design of similar aerators.