Computational modelling of free surface flow in intake structures using flow 3D software

Aybar, Akın
Intakes are inlet structures where fluid is accelerated to a certain flow velocity to provide required amount of water into a hydraulic system. Intake size and geometry affects the formation of flow patterns, which can be influential for hydraulic performance of the whole system. An experimental study is conducted by measuring velocity field in the hydraulic model of the head pond of a hydropower plant to investigate vortex formation. Vortex strength based on potential flow theory is calculated from the measured velocity field. It was shown that vortex strength increases with the submergence Froude number. The free surface flow in the head pond is simulated using Flow-3D software. Vortex strength calculations are repeated using the computational velocity distributions and compared to experimentally obtained values. Similar computations were carried on with some idealized pond geometries such as rectangular and circular.


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Ozbayoglu, E. M.; Miska, S. Z.; Takach, N.; Reed, T. (Informa UK Limited, 2009-01-01)
In this study, a layered cuttings transport model is developed for high-angle and horizontal wells, which can be used for incompressible non-Newtonian fluids as well as compressible non-Newtonian fluids (i.e., foams). The effects of major drilling parameters, such as flow rate, rate of penetration, fluid density, viscosity, gas ratio, cuttings size, cuttings density, wellbore inclination and eccentricity of the drillsting on cuttings transport efficiency are analyzed. The major findings from this study are,...
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Çalamak, Melih; Bozkuş, Zafer; Department of Civil Engineering (2010)
Waterhammer is an unsteady hydraulic problem which is commonly found in closed conduits of hydropower plants, water distribution networks and liquid pipeline systems. Due to either a malfunction of the system or inadequate operation conditions, pipeline may collapse or burst erratically resulting in substantial damages, and human losses in some cases. In this thesis, time dependent flow situations in the penstocks of small hydropower plants are investigated. A software, HAMMER, that utilizes method of chara...
Investigation of critical submergence at single and multiple- horizontal intake structures having air- entraining vortices
Gökmener, Serkan; Göğüş, Mustafa; Department of Civil Engineering (2015)
In this experimental study the variation of the critical submergence of air- entraining vortices with important flow and geometrical parameters were investigated at single and multiple- horizontal intake structures. In the scope of this study, three identical pipes of diameter Di=0.265 m were tested at a wide range of discharge with varying side wall clearances under symmetrical and asymmetrical approach flow conditions. Using dimensional analysis dimensionless equation was developed for critical submergenc...
Citation Formats
A. Aybar, “Computational modelling of free surface flow in intake structures using flow 3D software,” M.S. - Master of Science, Middle East Technical University, 2012.