Hydraulics Near Unscreened Diversion Pipes in Open Channels: Large Flume Experiments

Download
2017-04-01
Ercan, Ali
Kavvas, M. Levent
Carr, Kara
Hockett, Zachary
Bandeh, Hossein
Mussen, Timothy D.
Cocherell, Dennis
Poletto, Jamilynn B.
Cech, Joseph J.
Fangue, Nann A.
Most of the water diversions on the Sacramento and San Joaquin Rivers (California, United States) and their tributaries are currently unscreened. These unscreened diversions are commonly used for irrigation and are potentially harmful to migrating and resident fishes. A large flume (test section: 18.29 m long, 3.05 m wide and 3.20 m high) was used to investigate the hydraulic fields near an unscreened water diversion under ecologically and hydraulically relevant diversion rates and channel flow characteristics. We investigated all combinations of three diversion rates (0.28, 0.42, and 0.57 m(3)/s) and three sweeping velocities (0.15, 0.38, and 0.61 m/s), with one additional test at 0.71 m(3)/s and 0.15 m/s. We measured the three-dimensional velocity field at seven cross sections near a diversion pipe and constructed regression equations of the observed maximum velocities near the pipe. Because the velocity components in three directions (longitudinal, transverse, and vertical) were significantly greater near the diversion pipe inlet compared with those farther from it, they cannot be neglected in the modeling and design of fish guidance and protection devices for diversion pipes. Our results should be of great value in quantifying the hydraulic fields that are formed around fish guidance devices to design more effective protection for fishes from entrainment into unscreened water-diversion pipes.
JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION

Suggestions

Numerical modelling of free surface flows on round vertical slot fish passes
Koçal, Çiğdem; Köken, Mete; Department of Civil Engineering (2019)
Dams and weirs built on the rivers block the flow and prevent fishes from migrating along the river. To overcome this problem, fish passes can be built at those blocked locations along the river by providing a gently sloped channel with low flow rates and enough water depth to allow fish to ascend. Considering the design process, understanding the hydrodynamics inside fish pass structures is important. By using three dimensional numerical simulations, parameters like flow rates, velocity, turbulence and wat...
Numerical simulation of free surface flows at fish passages /
Özkaya, Kerem; Köken, Mete; Department of Civil Engineering (2014)
Hydroelectric dams build on the rivers block most of the flow section and leaves no space for the migrating fish along the rivers. Fish passages are built along the river at those locations to overcome this problem. Understanding the hydrodynamics inside these structures is essential in the design process. Parameters like discharge, velocity, acceleration and turbulence inside the fish passage can be obtained using three dimensional numerical simulations. Change in these parameters is investigated for diffe...
Numerical modeling of shoreline changes around Manavgat river mouth
Al Saleh, Fatıma; Özhan, Erdal; Department of Aerospace Engineering (2004)
River mouths are very active coastal regions. Continuous sediment supply by the river and the movement by wave action cause the shoreline to change in time and space. Modeling of shoreline changes is an essential step before the design of any coastal engineering project. This research aimed to develop a system of numerical models to present the shoreline changes around a river mouth. The system of numerical models has three components: 1) modeling of nearshore wave characteristics, 2) modeling of longshore ...
Hydraulic characteristics of tyrolean weirs having steel racks and circular-perforated entry
Şahiner, Halit; Göğüş, Mustafa; Department of Civil Engineering (2012)
Tyrolean type water-intake structures are commonly used on mountain rivers to supply water to hydropower stations. The amount of water to be diverted from the main channel is the major concern in these kind of structures and should not be less than the design discharge. In this study a physical model of a Tyrolean type water-intake structure was built at the laboratory and the diverted flow from the main channel through the intake structure having steel racks and perforated plates of different types were me...
Biomanipulation as a Restoration Tool to Combat Eutrophication: Recent Advances and Future Challenges
Jeppesen, Erik; Sondergaard, Martin; Lauridsen, Torben L.; Davidson, Thomas A.; Liu, Zhengwen; Mazzeo, Nestor; Trochine, Carolina; Özkan, Korhan; Jensen, Henning S.; Trolle, Dennis; Starling, Fernando; Lazzaro, Xavier; Johansson, Liselotte S.; Bjerring, Rikke; Liboriussen, Lone; Larsen, Soren E.; Landkildehus, Frank; Egemose, Sara; Meerhoff, Mariana (2012-01-01)
Eutrophication resulting from high nutrient loading has been the paramount environmental problem for lakes world-wide for the past four decades. Efforts are being made in many parts of the world to reduce external nutrient loading via improved wastewater treatment or diversion of nutrient-rich inflows. However, even after a reduction of the external phosphorus loading, the effects obtained may be unsatisfactory. This may reflect an insufficient reduction in the external nutrient loading to effectively limit...
Citation Formats
A. Ercan et al., “Hydraulics Near Unscreened Diversion Pipes in Open Channels: Large Flume Experiments,” JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, vol. 53, no. 2, pp. 431–441, 2017, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/101082.