Discussion on outlet layout and spillway energy dissipation for Bakun hydropower project

The Bakun outlets are characterized by high head,large flow velocity,severe cavitation and erosion,and long operation time,great construction difficulties and technical challenges.In design,the alternative of butterfly valve,cone valve and oval stilling chamber is selected through comparison of many options,two hydraulic model tests and consulting by experts from China and abroad,which solves the problems of hydraulics and structure effectively and reasonably.The design alternative is finally approved by the Employer,the Engineer's Representative and experts of SCP.Currently,the outlets construction is completed and will be put into operation soon.