Stilling Basins
Type II and Type III stilling basins reduce the energy of the flow discharging from a spillway and allow the water to enter the outlet channel at a reduced velocity. Type II basins contain chute blocks at the upstream end and a dentated (tooth-like) endsill. Baffle piers are not used in a Type II basin because of the high velocity water entering the basin. Type III energy dissipators can be used if the entering flow velocity is not high (less than 50 feet per second (Hydraulic Design of Stilling Basins and Energy Dissipators, USBR, 1984). Type III basins contain baffle piers which are located on the stilling basin apron downstream of the chute blocks. Located at the end of both types of USBR stilling basins is an endsill, which may be leveled or sloped, that creates a tailwater to reduce the velocity of the flow leaving the basin. [1]
Examples
See examples of energy dissipation using stilling basins
Citations:
Revision ID: 5504
Revision Date: 12/13/2022