<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Subcritical flows over highway and railway embankments, commonly encountered during flood events, can be treated like submerged flows over trapezoidal-shaped weirs. In earlier studies, the equation of the submerged-flow discharge for such types of weirs was developed as a function of the degree of submergence and free-flow discharge. However, the application of this equation in practice requires a pre-determined discharge from experiments performed under free-flowconditions. In this study, a discharge equation was deduced from the streamwise momentum balance equation, which overcomes the drawback of the previous approaches. The results of the validation demonstrated that the proposed equation is capable of predicting the submerged-flow discharge of a trapezoidal-shaped weir within ±6.0% of the measured value. Furthermore, the most prominent features of the submerged overflows were examined by systematically analyzing the experimental data. For such flows, the free-surface and bed-pressure profiles are self-similar only over the upstream face of the weir. Results of this investigation confirmed that the degree of submergence and the slope of the downstream weir face significantly affect the characteristics of the submerged flow, but the effect of the latter on the non-modular discharge is marginal.</p>
</abstract>

Subcritical flows over highway and railway embankments, commonly encountered during flood events, can be treated like submerged flows over trapezoidal-shaped weirs. In earlier studies, the equation of the submerged-flow discharge for such types of weirs was developed as a function of the degree of submergence and free-flow discharge. However, the application of this equation in practice requires a pre-determined discharge from experiments performed under free-flowconditions. In this study, a discharge equation was deduced from the streamwise momentum balance equation, which overcomes the drawback of the previous approaches. The results of the validation demonstrated that the proposed equation is capable of predicting the submerged-flow discharge of a trapezoidal-shaped weir within ±6.0% of the measured value. Furthermore, the most prominent features of the submerged overflows were examined by systematically analyzing the experimental data. For such flows, the free-surface and bed-pressure profiles are self-similar only over the upstream face of the weir. Results of this investigation confirmed that the degree of submergence and the slope of the downstream weir face significantly affect the characteristics of the submerged flow, but the effect of the latter on the non-modular discharge is marginal.

On the Hydraulic Characteristics of Submerged Flow over Trapezoidal-Shaped Weirs

Archives of Hydro-Engineering and Environmental Mechanics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

{"article-title":"On the Hydraulic Characteristics of Submerged Flow over Trapezoidal-Shaped Weirs"}

Subcritical flows over highway and railway embankments, commonly encountered during flood events, can be treated like submerged flows over trapezoidal-shaped...

On the Hydraulic Characteristics of Submerged Flow over Trapezoidal-Shaped Weirs

Published Online: Mar 08, 2023

Page range: 1 - 16

Received: Nov 25, 2022

DOI: https://doi.org/10.2478/heem-2023-0001

Keywords
submerged-flow discharge, hydraulic structure, trapezoidal-shaped weir, flow measurement, subcritical flow, modular limit

© 2023 Yebegaeshet T. Zerihun, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

On the Hydraulic Characteristics of Submerged Flow over Trapezoidal-Shaped Weirs

Published Online: Mar 08, 2023

Page range: 1 - 16

Received: Nov 25, 2022

DOI: https://doi.org/10.2478/heem-2023-0001

Keywordssubmerged-flow discharge, hydraulic structure, trapezoidal-shaped weir, flow measurement, subcritical flow, modular limit

© 2023 Yebegaeshet T. Zerihun, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
submerged-flow discharge, hydraulic structure, trapezoidal-shaped weir, flow measurement, subcritical flow, modular limit