Energy dissipation of free falling jets - literature review

The provision of means of spilling excess water from behind dams has long been a problem for design engineers. The difficulty lies in conveying the flow to the downstream river bed in such a way that excessive scour is prevented. Of the methods available the use of free falling jets is becoming more common due to the simplicity and economy of the structures required. Various methods of dissipating the energy of free falling jets are reviewed. These include the forced disintegration of a jet by devices on the dam face, increased air resistance due to jet trajectory consideration, and at the base of the dam energy dissipation in an increased tailwater or plunge pool.