Clear Water Local Scour by Submerged Three-Dimensional Wall Jets: Effect of Tailwater Depth
Publication: Journal of Hydraulic Engineering
Volume 132, Issue 6
Abstract
The present study deals with scour caused by three-dimensional jets issuing from a square cross-section nozzle onto a noncohesive sand bed. Experiments were conducted using two different nozzles and three tailwater depths. The densimetric Froude number was maintained below ten, while the jet expansion ratio was held greater than ten. The results indicate that the densimetric Froude number, tailwater depth, and grain size-to-nozzle width ratio, all have an influence on the extent of scour. However, each parameter has a dominant influence at different flow conditions. For example, at values of densimetric Froude numbers less than five, nondimensional tailwater depth and grain size-to-nozzle width ratio have no effect on the maximum depth of scour. At higher densimetric Froude numbers, the effect of tailwater depth appears to be important at larger values of grain size-to-nozzle width ratio. A set of scaling parameters based on nozzle hydraulic radius, grain size, and densimetric Froude number provides for a better scaling of the time variation of the scour parameters.
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References
Ade, F., and Rajaratnam, N. (1998). “Generalized study of erosion by circular horizontal turbulent jets.” J. Hydraul. Res., 36(4), 613–635.
Aderibigbe, O., and Rajaratnam, N. (1998). “Effect of sediment gradation on erosion by plane turbulent wall jets.” J. Hydraul. Eng., 124(10), 1034–1042.
Ali, K. H. M., and Lim, S. Y. (1986). “Local scour caused by submerged wall jets.” Proc. Inst. Civ. Eng., Water and Maritime Eng., Part 2, 81, 607–645.
Balachandar, R., Kells, J. A., and Thiessen, R. J. (2000). “The effect of tailwater depth on the dynamics of local scour.” Can. J. Civ. Eng., 27(1), 138–150.
Blaisdell, F., and Anderson, C. L. (1988). “A comprehensive generalized study of scour at cantilevered pipe outlets.” J. Hydraul. Res., 26(4), 357–376.
Breusers, H. N. C., and Raudkivi, A. J. (1991). Scouring, hydraulic structure design manual, A. A. Balkema, Rotterdam, The Netherlands.
Chiew, Y. M., and Lim, S. Y. (1996). “Local scour: By a deeply submerged horizontal circular jet.” J. Hydraul. Eng., 122(9), 529–532.
Faruque, M. A. A. (2004). “Transient local scour by submerged three dimensional wall jets: Effect of tailwater depth.” MASc, thesis, Univ. of Windsor, Windsor, Canada.
Lim, S. Y. (1995). “Scour below unsubmerged full-flowing culvert outlets.” Proc. Inst. Civ. Eng., Waters. Maritime Energ., 112(2), 136–149.
Rajaratnam, N. (1981). “Erosion by plane turbulent jets.” J. Hydraul. Res. 19(4), 339–358.
Rajaratnam, N., and Berry, B. (1977). “Erosion by circular turbulent wall jets.” J. Hydraul. Res., 15(3), 277–289.
Rajaratnam, N., and Diebel, M. (1981). “Erosion below culvert-like structure.” Proc., 5th Canadian Hydrotechnical Conf., CSCE, Fredericton, New Brunswick, 469–484.
Rajaratnam, N., and Macdougall, R. K. (1983). “Erosion by plane wall jets with minimum tailwater.” J. Hydraul. Eng., 109(7), 1061–1064.
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© 2006 ASCE.
History
Received: May 18, 2004
Accepted: Aug 26, 2005
Published online: Jun 1, 2006
Published in print: Jun 2006
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