Investigation of critical submergence at single and multiple- horizontal intake structures having air- entraining vortices

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2015
Gökmener, Serkan
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 submergence as a function of relevant flow and geometrical parameters. Regression analysis was used to derive empirical equations for the critical submergence. Moreover, these empirical equations were compared with the similar studies in the literature. Results of the experiments show that, for a given Froude number, the critical submergence values are higher for multiple water intake structures than those of single water intake structures. By using these equations it is possible to determine the required critical submergence depths above which there will be no air- entraining vortices, at single and multiple- horizontal intakes within the ranges of dimensionless parameters tested in this study. Moreover, floating rafts at different sizes were tested as anti- vortex devices to prevent the formation of air- entraining vortices and very successful results were achieved.

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Citation Formats
S. Gökmener, “Investigation of critical submergence at single and multiple- horizontal intake structures having air- entraining vortices,” M.S. - Master of Science, Middle East Technical University, 2015.