白鹤滩水电站尾水洞明满流段优化试验研究  

Experimental study on optimum of the free-surface-pressurized tailrace tunnel in Baihetan Hydropower Station

作　　者：孙洪亮 陈益民 杨飞 侯博 Sun Hongliang;Chen Yimin;Yang Fei;Hou Bo

机构地区：[1]中国电建集团华东勘测设计研究院有限公司

出　　处：《中国水利》2019年第18期80-83,共4页China Water Resources

摘　　要：白鹤滩水电站尾水隧洞末端部分洞段由导流洞改建而成,尾水位较低时,存在明满流现象,对输水系统安全有重要影响。本文采用模型试验方法,对明满流段的流态及体型优化进行研究。结果表明:过渡过程中,尾水洞内正反向水流相叠加,产生水面涌波,触顶后形成眀满流,并伴随压力脉动现象。脉动压力的极值远小于隧洞衬砌压力的设计值73.5 m,对尾水隧洞衬砌段结构影响较小。结构优化研究表明在尾水隧洞出口设置逆坡堰及优化衔接段坡度,可有效改善明满流流态。The end part of Baihetan hydropower station tailrace tunnel is reconstructed from diversion tunnel.When the tailrace water level is low,there exists free-surface-pressurized flow phenomenon,which has an important impact on the safety of water conveyance system.In this paper,the model test method is used to study the flow characteristic and structure optimization of the free-surface-pressurized tailrace tunnel.The results show that during the transition process,the forward and reverse water flows in tailrace tunnel are superimposed,resulting in a water surface surge wave,which forms free-surface-pressurized flow after the surge wave touching the tunnel top,accompanied by pressure pulsation.The extreme value of pressure pulsation is much less than the design value of tunnel lining pressure of 73.5 meters,which has little influence on the structure of tailrace tunnel lining section.Structural optimization study shows that the free-surface-pressurized flow regime can be effectively improved by setting up inverse slope weir at the outlet of tailrace tunnel and optimizing the gradient of the connecting section.

关 键 词：白鹤滩水电站 尾水隧洞 明满流 模型试验 结构优化 

分 类 号：TV7[水利工程—水利水电工程] TV134.3