Effect of double gate mechanism on scour hole characteristics

Basyoni, Asmaa; Mostafa, Gamal; Elnikhili, Eman

doi:10.21608/eijest.2021.92733.1096

Effect of double gate mechanism on scour hole characteristics

Document Type : Original Article

Authors

¹ zagazig university

² Water Department, Faculty of Engineering, Zagazig University, Zagazig

10.21608/eijest.2021.92733.1096

Abstract

Local scour due to free hydraulic jump downstream hydraulic structures may cause damage or complete failure of these structures, so controlling of this phenomenon is very important. The main goal of this study is to reduce the characteristics of a scour hole downstream double gates system. Using a plate in certain positions have to build downstream of the model as a typical engineering precautions to minimize the effect of erosion. The optimum precaution plate position is a key parameter in the design of this type of hydraulic structures. The proposed model of the double vertical gates distributed the passing discharge via two vents, in which the lower discharge passed under the lower gate, while the upper discharge was the passing discharge between the two vertical gates. Using the relative gate opening of 0.25 and fixing the plate at relative vertical position Z/LB of 0.00, 0.027, 0.047 and 0.067. The plate at a relative vertical position of 0.067 was the optimal position causing an increasing of the relative energy loss by 1.72% and the relative maximum scour depth decreased by 1.69% compared to the case of no plate downstream the gates. The measured results matched closely with the estimated results from the developed empirical equations.

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