向家坝水电站地下厂房变顶高尾水系统研究

为了满足电站的调节保证要求，减小地下洞室群的规模，向家坝水电站地下厂房采用了特殊的尾水系统布置方案，即变顶高尾水洞方案，取消了尾水调压室。在研究水电站变顶高尾水洞基本工作原理的基础上，提出了向家坝水电站右岸地下厂房变顶高尾水洞布置方案研究的基本思路和具体步骤，论证了采用变顶高尾水洞方案的可行性和合理性。

Study on the tailrace system with the ceiling height changes of underground powerhouse of Xiangjiaba Hydroelectric Project

In order to meet the regulation guarantee requirements, and to minimize the size of underground cavern complex, the special tailrace system scheme (i.e., a tailrace tunnel with ceiling height changes and a cancellation of tailrace surge chamber) has been adopted for the Xiangjiaba Hydroelectric Project. This paper presents the basic working principles and design philosophy of the special tailrace system, and justifies the availability and rationality of the scheme, based on the studies of basic working philosophy of a tailrace tunnel with ceiling height changes.