Scour Around Spherical Bodies and Self-Burial
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 131, Issue 1
Abstract
This paper summarizes the results of an experimental study on scour around spherical bodies and self-burial in steady current and in waves. The equilibrium scour depth below a fixed sphere in steady current for live-bed conditions was found to be , being the sphere diameter. The effect of the Shields parameter, , and that of the position of the sphere with respect to the bed, , were investigated. It was found that, under live-bed conditions, the effect of is quite weak. It was also found that the effect of is significant. No scour occurs when . It was demonstrated that, in the case of waves, the Keulegan-Carpenter number, , is the main parameter that governs the equilibrium scour depth. is always smaller in waves than in steady currents. Regarding the self-burial, the equilibrium self-burial depth in steady current was found to be . The self-burial depth in waves is governed by , similar to the scour depth for a fixed sphere. is always smaller in waves than in steady currents. The experiments indicated that the time scale of both the scour process and the self-burial process is a function of in the case of steady current, and and in the case of waves.
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Acknowledgments
This study has been partially supported by the five-year (1999–2004) Framework Program “Computational Hydrodynamics” of the Danish Technical Research Council (STVF), and by the European Commission Research Directorates’ FP5 specific program “Energy, Environment, and Sustainable Development,” Contract No. EVK3-CT-2000-00041, Environmental Design of Low Crested Coastal Defence Structures (DELOS).
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© 2005 ASCE.
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Received: Oct 7, 2003
Accepted: Jul 20, 2004
Published online: Jan 1, 2005
Published in print: Jan 2005
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