Visualization Tests on Scour Rates below Pipelines in Steady Currents
Publication: Journal of Hydraulic Engineering
Volume 145, Issue 4
Abstract
This paper presents visible experimental results of three-dimensional scour beneath pipelines. A miniature camera installed inside a transparent pipeline was used to observe the scour propagation process under a pipeline in steady currents. The data showed that the average scour hole propagation rate decreased nonlinearly with increasing pipeline embedment. The scour propagation rate increased with the Froude number at an increasing climb rate. The critical flow velocity for scour propagation was investigated. The critical velocity increased with increased pipeline embedment and the flow depth. It was lower than the critical velocity of sediment incipient motion. An empirical equation for the variation of the Froude number with the scour propagation rate was proposed for pipeline embedment ratios and relative flow depths .
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Acknowledgments
This work was supported in part by the Chinese National Natural Science Foundation Council under Grant Nos. 11172213 and 51479137. The first author acknowledges the support from the China Scholarship Council (Grant No. 201806260166). Tsun-ming Wong and Ting Lin, two undergraduate students from the College of Civil Engineering, Tongji University, also contributed to the experiments.
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Information & Authors
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Published In
Journal of Hydraulic Engineering
Volume 145 • Issue 4 • April 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Jun 26, 2018
Accepted: Sep 12, 2018
Published online: Jan 21, 2019
Published in print: Apr 1, 2019
Discussion open until: Jun 21, 2019
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