Two-Dimensional Scour Hole Problem: Role of Fluid Structures
Publication: Journal of Hydraulic Engineering
Volume 133, Issue 4
Abstract
An experimental program was carried out to understand scour caused by a plane wall jet. A two-dimensional laser Doppler anemometer was used to characterize the velocity field at various locations in the scour hole region. Observations indicate that different types of flow structures influence scour at different time periods. Based on the present tests, the entire test duration is divided into five time zones. Following vigorous scour caused principally by jet shear forces and impingement at the start of the test and during early time periods, the flow was characterized by the presence of longitudinal axial vortices, turbulent bursts, and movement of the jet impingement point during the later stages. Attempts were made to distinguish the fluid structures at asymptotic conditions. The scour hole region was characterized by the presence of randomly forming and disappearing streaks, laterally located concave shaped depressions, rolling and ejection of the bed material. Through analysis of higher order moments and quadrant decomposition, sweep and ejection type events were observed, which can potentially contribute to scour.
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References
Ali, K. H. M., and Lim, S. Y. (1986). “Local scour caused by submerged wall jets.” Proc. Inst. Civ. Eng., Part 2. Res. Theory, 81, 607–645.
Annandale, G. W. (2004). “Keynote address.” 2nd Int. Conf. on Scour and Erosion, Surbana, Singapore.
Balachandar, R., and Kells, J. A. (1997). “Local channel scour in uniformly graded sediments: The time-scale problem.” Can. J. Civ. Eng., 24(5), 799–807.
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.
Bey, A. (2005). “Two-dimensional scour hole problem.” MASc thesis, Dept. of Civil and Environmental Engineering, Univ. of Windsor, Windsor, Ont., Canada.
Chatterjee, S. S., Ghosh, S. N., and Chatterjee, M. (1994). “Local scour due to submerged horizontal jet.” J. Hydraul. Eng., 120(8), 973–992.
Deshpande, N. (2004). “Effects of submergence and test startup conditions on local scour by plane turbulent wall jets.” MASc, thesis, Univ. of Windsor, Windsor, Ont., Canada.
Faruque, M. A. A. (2004). “Transient local scour by submerged three dimensional wall jets: Effect of tailwater depth.” MASc, thesis, Univ. of Windsor, Windsor, Ont., Canada.
Hoffmans, G. J. C. M., and Booij, R. (1993). “Two-dimensional mathematical modeling of local scour holes.” J. Hydraul. Res., 31(5), 615–634.
Hogg, A. J., Huppert, H. E., and Dade, W. B. (1997). “Erosion by planar turbulent wall jets.” J. Fluid Mech., 338, 317–340.
Hopfinger, E. J., Kurniawan, A., Graf, W. H., and Lemmin, U. (2004). “Sediment erosion by Götler vortices: The scour problem.” J. Fluid Mech., 520, 327–342.
Johnston, A. J. (1990). “Scourhole developments in shallow tailwater.” J. Hydraul. Res., 28(3), 341–354.
Karim, O. A., and Ali, K. H. M. (2000). “Prediction of flow patterns in local holes caused by turbulent water jets.” J. Hydraul. Res., 38(4), 279–287.
Karlsson, R. L., Erikson, J., and Persson, J. (1993). “LDV measurements in a plane wall jet in a large enclosure.” Laser techniques and applications in fluid mechanics, R. J. Adrian, et al., eds., Springer, Berlin.
Kells, J. A., Balachandar, R., and Hagel, K. P. (2001). “Effect of grain size on local channel scour below a sluice gate.” Can. J. Civ. Eng., 28(3), 440–451.
Krogstad, P., and Antonia, R. (1999). “Surface roughness effects in turbulent boundary layers.” Exp. Fluids, 27(5), 450–460.
Mohamed, M. S., and McCorquodale, J. A. (1992). “Short-term local scour.” J. Hydraul. Res., 30(5), 685–699.
Quinn, W. R., and Militzer, J. (1988). “Experimental and numerical study of a turbulent free square jet.” Phys. Fluids, 31(5), 1017–1025.
Rajaratnam, N. (1981). “Erosion by plane turbulent jets.” J. Hydraul. Res., 19(4), 339–358.
Rajaratnam, N., Aderibigbe, O., and Pochylko, D. (1995). “Erosion of sand beds by oblique plane water jets.” Proc. Inst. Civ. Eng., Waters. Maritime Energ., 112(1), 31–38.
Rajaratnam, N., and Berry, B. (1977). “Erosion by circular turbulent wall jets.” J. Hydraul. Res., 15(3), 277–289.
Rajaratnam, N., and Humphries, J. A. (1984). “Turbulent non-buoyant surface jets.” J. Hydraul. Res., 22(2), 103–115.
Rajaratnam, N., and Macdougall, R. K. (1983). “Erosion by plane wall jets with minimum tailwater.” J. Hydraul. Eng., 109(7), 1061–1064.
Tachie, M. F. (2000). “Open channel turbulent boundary layers and wall jets on rough surfaces.” Ph.D. thesis, Univ. of Saskatchewan, Saskatchewan, Canada.
Wu, S., and Rajaratnam, N. (1995). “Free jumps, submerged jumps, and wall jets.” J. Hydraul. Res., 33(2), 197–212.
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© 2007 ASCE.
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Received: Apr 1, 2005
Accepted: Sep 14, 2006
Published online: Apr 1, 2007
Published in print: Apr 2007
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