Scour Reduction by Air Injection: Flow Patterns and Turbulence
Publication: Journal of Hydraulic Engineering
Volume 142, Issue 3
Abstract
Experiments in a stilling basin model with air injected at its downstream end exhibited plunging flow resulting in a downward roller, return flow along the bottom, and a downstream near-bed flow after the plunging flow impingement point. Turbulence measurements showed that air injection reduces turbulence both at the exit of the stilling basin and near the downstream bed. Thus the effect of air injection as a modifier of the turbulence structure of the flow downstream of the stilling basin is postulated as a plausible explanation for the observed scour reduction.
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Acknowledgments
This study was partially funded by the South Florida Water Management District. We thank the following students who helped take the numerous velocity measurements: Mathew Edwards, Wesley Davis, Benjamin Doege, Lukas Morse, Mark Maguire, Jonathan Materni, Janet Gebauer, Allen Crum, Elizabeth Stempihar, Brittney Horton, Matt Kiehler, Rachael Barlock, Chelsea Fagen, and Eric Anderson.
References
Birjandi, A. H., and Bibeau, E. (2009). “Bubble effects on the acoustic Doppler velocimeter (ADV) measurements.” Proc., ASME Fluids Engineering Div. Summer Conf., Vol. 2, ASME, New York, 27–32.
Champagne, T. M. (2011). “Physical modeling of air injection as a scour remediation technique near gated weir stilling basins.” M.S. thesis, Michigan Technical Univ., Houghton, MI.
Ettema, R., Melville, B. W., and Barkdoll, B. (1998). “Scale effect in pier-scour experiments.” J. Hydraul. Eng., 639–642.
Goring, D. G., and Nikora, N. I. (2002). “Despiking acoustic Doppler velocimeter data.” J. Hydraul. Eng., 117–126.
Hong, S. H., Kim, S. J., Sturm, T., Stoesser, T., and Gonzalez-Castro, J. A. (2010). “Effect of low tailwater during drought on scour conditions downstream of an ogee spillway.” Proc., River Flow Int. Conf., IAHR, Madrid, Spain.
Jia, Y., Tadanori, K., and Wang, S. S. Y. (2001). “Simulation of scour process in plunging pool of loose bed-material.” J. Hydraul. Eng., 127(3), 219–229.
Kumar, A., and Kothyari, U. C. (2012). “Three-dimensional flow characteristics within the scour hole around circular uniform and compound piers.” J. Hydraul. Eng., 420–429.
Liu, M., Rajaratnam, N., and Zhu, D. Z. (2004). “Turbulence structure of hydraulic jumps of low froude numbers.” J. Hydraul. Eng., 511–520.
Liu, P. Q., Dong, J. R., and Yu, C. (1998). “Experimental investigation of fluctuation uplift on rock blocks at the bottom of the scour pool downstream of Three-Gorges spillway.” J. Hydraul. Res., 36(1), 55–68.
Mori, N., Suzuki, T., and Kakuno, S. (2007). “Noise of acoustic Doppler velocimeter data in bubbly flows.” J. Eng. Mech., 122–125.
Nielsen, K. D., Muste, M., and Weber, L. (1998). “Plunging jet measurement improvements using ADV.” Proc., Int. Water Research Engineering Congress, ASCE, Reston, VA, 832–837.
Reichstetter, M., and Chanson, H. (2013). “Unsteady turbulent properties in negative waves in open channels.” Eur. J. Mech. B/Fluids, 37, 1–9.
Stein, O. R., Julien, P. Y., and Alonso, C. V. (1993). “Mechanics of jet scour downstream of a headcut.” J. Hydraul. Res., 31(6), 723–738.
Strom, K. B., and Papanicolaou, A. N. (2007). “ADV measurements around a cluster microform in a shallow mountain stream.” J. Hydraul. Eng., 1379–1389.
Wahl, T. L. (2000). “Analyzing ADV data using WinADV.” 2000 Joint Conf. on Water Resources Engineering and Water Resources Planning & Management, ASCE, Reston, VA, 1–10.
Wang, H., Felder, S., and Chanson, H. (2014). “An experimental study of turbulent two-phase flow in hydraulic jumps and application of a triple decomposition technique.” Exp. Fluids, 55(7), 1–18.
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Published In
Journal of Hydraulic Engineering
Volume 142 • Issue 3 • March 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Oct 1, 2013
Accepted: Jun 10, 2015
Published online: Nov 4, 2015
Published in print: Mar 1, 2016
Discussion open until: Apr 4, 2016
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