Velocity Distributions around Blocked Trash Racks
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VIEW THE REPLYPublication: Journal of Irrigation and Drainage Engineering
Volume 147, Issue 9
Abstract
Transported debris in open channels can lead to accumulations and, therefore, cause blockages at trash racks. Velocity distributions and flow patterns change because of these blockages and may lead to geomorphic condition evolution around the blocked racks. Despite numerous investigations related to racks, systematic studies of velocity distributions around rack accumulations of debris blockage are missing. The debris accumulations were simulated using a horizontal plate blockage. The experiments were performed for different blockage ratios (, 0.25, 0.32, 0.45, 0.50, 0.64, and 0.69) and various approach Froude numbers (, 0.07, 0.08, 0.10, and 0.12) to analyze the up- and downstream velocity fields in the middle and near the wall in the flow direction around the rack. Overall, the results show that the velocity distributions were influenced by the blockage and new velocity results are provided for both up- and downstream of the rack. Additionally, a new average velocity equation is proposed for a rack with attached plate of large wood that considers the effects of blockage ratios and Froude numbers.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
The presented experimental work was done at the Hydraulics Laboratory of Channel Maintenance Research Institute, National Water Research Center (NWRC), Egypt. The author appreciates the technical support of CMRI.
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Journal of Irrigation and Drainage Engineering
Volume 147 • Issue 9 • September 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Sep 5, 2020
Accepted: Apr 26, 2021
Published online: Jul 9, 2021
Published in print: Sep 1, 2021
Discussion open until: Dec 9, 2021
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Cited by
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