Hostname: page-component-745bb68f8f-lrblm Total loading time: 0 Render date: 2025-01-24T21:57:33.697Z Has data issue: false hasContentIssue false
  • English
  • Français

Coherent structures in wave boundary layers. Part 1. Oscillatory motion

Published online by Cambridge University Press:  08 March 2010

STEFAN CARSTENSEN ,
B. MUTLU SUMER  and
JØRGEN FREDSØE
STEFAN CARSTENSEN
Affiliation:
Technical University of Denmark, DTU Mekanik, Section of Coastal, Maritime and Structural Engineering, Building 403, 2800 Kgs. Lyngby, Denmark
B. MUTLU SUMER*
Affiliation:
Technical University of Denmark, DTU Mekanik, Section of Coastal, Maritime and Structural Engineering, Building 403, 2800 Kgs. Lyngby, Denmark
JØRGEN FREDSØE
Affiliation:
Technical University of Denmark, DTU Mekanik, Section of Coastal, Maritime and Structural Engineering, Building 403, 2800 Kgs. Lyngby, Denmark
*
‡Email address for correspondence: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

This work concerns oscillatory boundary layers over smooth beds. It comprises combined visual and quantitative techniques including bed shear stress measurements. The experiments were carried out in an oscillating water tunnel. The experiments reveal two significant coherent flow structures: (i) Vortex tubes, essentially two-dimensional vortices close to the bed extending across the width of the boundary-layer flow, caused by an inflectional-point shear layer instability. The imprint of these vortices in the bed shear stress is a series of small, insignificant kinks and dips. (ii) Turbulent spots, isolated arrowhead-shaped areas close to the bed in an otherwise laminar boundary layer where the flow ‘bursts’ with violent oscillations. The emergence of the turbulent spots marks the onset of turbulence. Turbulent spots cause single or multiple violent spikes in the bed shear stress signal, which has profound implications for sediment transport (in both the laboratory and the field). The experiments also show that similar coherent flow structures exist in the case of combined oscillatory flow and current.

JFM classification

Boundary Layers: Boundary layer stability Turbulent Flows: Turbulent transition
Type
Papers
Information
Journal of Fluid Mechanics , Volume 646 , 10 March 2010 , pp. 169 - 206
Copyright
Copyright © Cambridge University Press 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

†

Present address: DHI, Agern Alle 5, 2970 Hørsholm, Denmark.

References

REFERENCES

Akhavan, R., Kamm, R. D. & Shapiro, A. H. 1991 a An investigation of transition to turbulence in bounded oscillatory Stokes flows. Part 1. Experiments. J. Fluid Mech. 225, 395–422.Google Scholar
Akhavan, R., Kamm, R. D. & Shapiro, A. H. 1991 b An investigation of transition to turbulence in bounded oscillatory Stokes flows. Part 2. Numerical simulations. J. Fluid Mech. 225, 423–444.Google Scholar
Batchelor, G. K. 1967 An Introduction to Fluid Dynamics. Cambridge University Press.Google Scholar
Bernall, L. P. 1981 The coherent structures of turbulent mixing layers. PhD thesis, California Institute of Technology.Google Scholar
Blennerhassett, P. J. & Bassom, A. P. 2006 The linear stability of high-frequency oscillatory flow in a channel. J. Fluid Mech. 556, 1–25.Google Scholar
Blondeaux, P. & Seminara, G. 1979 Transizione incipiente al fondo di un'onda di gravita. Rendiconti Accad. Naz. Lincei 67, 407–417.Google Scholar
Blondeaux, P. & Vittori, G. 1994 Wall imperfections as a triggering mechanism for Stokes-layer transition. J. Fluid Mech. 264, 107–135.Google Scholar
Blondeaux, P. & Vittori, G. 1999 Boundary layer and sediment dynamics under sea waves. In Advances in Coastal and Ocean Engineering (ed. Liu, P. L.-F.), vol. 4, pp. 133–190. World Scientific.Google Scholar
Browand, F. 1966 An experimental investigation of instability of an incompressible, separated shear layer. J. Fluid Mech. 26, 281–307.Google Scholar
Browand, F. & Plocher, D. A. 1985 Image processing for sediment transport. In 21st IAHR Congress, pp. 19–23. Melbourne, Australia.Google Scholar
Cantwell, B. J. 1981 Organized motion in turbulent flow. Annu. Rev. Fluid Mech. 13, 457–515.Google Scholar
Carstensen, S. 2006 Experimental investigation of coherent structures in wave boundary layers. PhD thesis. Technical University of Denmark, DTU Mekanik, Section of Coastal, Maritime and Structural Engineering.Google Scholar
Chambers, F. & Thomas, A. 1983 Turbulent spots, wave packets and growth. Phys. Fluids 26 (5), 1160–1162.Google Scholar
Costamagna, P., Vittori, G. & Blondeaux, P. 2003 Coherent structures in oscillatory boundary layers. J. Fluid Mech. 474, 1–33.Google Scholar
Das, D. & Arakeri, J. H. 1998 Transition to unsteady velocity profiles with reverse flow. J. Fluid Mech. 374, 251–283.Google Scholar
Dixen, M., Hatipoglu, F., Sumer, B. M. & Fredsøe, J. 2008 Wave boundary layer over a stone-covered bed. Coastal Engng 55, 1–20.Google Scholar
Emmons, H. 1951 Laminar–turbulent transition in boundary layer. J. Aeronaut. Sci. 18 (7), 490–498.Google Scholar
Fornarelli, F. & Vittori, G. 2009 Oscillatory boundary layer close to a rough wall. Eur. J. Mech. B. Fluids 28, 283–295.Google Scholar
Foster, D. L. 1997 Dynamics of the near shore wave bottom boundary layer. PhD thesis, Oregon State University.Google Scholar
Foster, D. L., Holman, R. A. & Beach, R. A. 1994 Sediment suspension events and shear instabilities in the bottom boundary layer. Coastal Dynamics 94. In Proc. Intl Conf. on the Role of the Large Scale Experiments in Coastal Research, ASCE (ed. Arcilla, A. S., Stive, M. F. & Kraus, N. C.), pp. 712–726. Universitat Politecnica de Catalunya, Barcelona, Spain.Google Scholar
Fredsøe, J. 1984 Turbulent boundary layer in wave-current motion. J. Hydraul. Engng ASCE 110, 1103–1120.Google Scholar
Fredsøe, J., Sumer, B. M., Kozakiewicz, A., Chua, L. H. C. & Deigaard, R. 2003 Effect of externally generated turbulence on wave boundary layer. Coastal Engng 49, 155–183.Google Scholar
Fuhrman, D. R., Fredsøe, J. & Sumer, B. M. 2009 a Bed slope effects on turbulent wave boundary layers: 1. Model validation and quantification of rough-turbulent results. J. Geophys. Res., 114, C03024, 1–16.Google Scholar
Fuhrman, D. R., Fredsøe, J. & Sumer, B. M. 2009 b Bed slope effects on turbulent wave boundary layers: 2. Comparison with skewness, asymmetry, and other effects. J. Geophys. Res., 114, C03025, 1–19.Google Scholar
Gad-el-Hak, M., Blackwelder, R. & Riley, J. 1981 On the growth of turbulent regions in laminar boundary layers. J. Fluid Mech. 110, 73–95.Google Scholar
Gilbrech, D. A. & Combs, G. D. 1963 Critical Reynolds numbers for incompressible pulsating flows in tubes. Develop. Theor. Appl. Mech. 1, 292–304.Google Scholar
Grass, A. J. 1971 Structural features of turbulent flow over smooth and rough boundaries. J. Fluid Mech. 50, 223–256.Google Scholar
Grant, W. D. & Madsen, O. S. 1979 Combined wave and current interaction with a rough bottom. J. Geophys. Res. 84, 1797–1808.Google Scholar
Hanratty, T. J. & Campbell, J. A. 1983 Measurement of wall shear stress. In Fluid Mechanics Measurements (ed. Goldstein, R. J.), pp. 559–615. Hemisphere.Google Scholar
Hayashi, T. & Ohashi, M. 1982 A dynamical and visual study on the oscillatory turbulent boundary layer. In Turbulent Shear Flows 3, pp. 18–33. Third International Symposium on Turbulent Shear Flows.Google Scholar
Hino, M., Kashiwayanagi, M., Nakayama, A. & Hara, T. 1983 Experiments on turbulence statistics and structure of reciprocating oscillatory flow. J. Fluid Mech. 131, 363–399.Google Scholar
Hino, M., Sawamoto, M. & Takasu, S. 1976 Experiments on transition to turbulence in an oscillatory pipe flow. J. Fluid Mech. 75 (2), 193–207.Google Scholar
Ho, C.-M. & Huerre, P. 1984 Perturbed free shear layers. Annu. Rev. Fluid Mech. 16, 365–424.Google Scholar
Jensen, B. L., Sumer, B. M. & Fredsøe, J. 1989 Turbulent oscillatory boundary layers at high Reynolds numbers. J. Fluid Mech. 206, 265–297.Google Scholar
Jimenez, J. & Moin, P. 1991 The numerical flow unit in the near-wall turbulence. J. Fluid Mech. 225, 213–240.Google Scholar
Justesen, P. 1988 Turbulent wave boundary layers. Series paper 41, Institute of Hydrodynamic and Hydraulic Engineering, Technical University of Denmark.Google Scholar
Kamphuis, J. W. 1975 Friction factor under oscillatory waves. J. Waterway, Port, Coastal and Ocean Engineering 101 (WW2), 135–144.Google Scholar
Kemp, P. H. & Simons, R. R. 1982 The interaction between waves and a turbulent current: waves propagating with the current. J. Fluid Mech. 116, 227–250.Google Scholar
Kemp, P. H. & Simons, R. R. 1983 The interaction between waves and a turbulent current: waves propagating against the current. J. Fluid Mech. 130, 73–89.Google Scholar
Kline, S. J., Reynolds, W. C., Schraub, F. A. & Runstadler, P. W. 1967 The structure of turbulent boundary layers. J. Fluid Mech. 30, 741–773.Google Scholar
Lodahl, C., Sumer, B. M. & Fredsøe, J. 1998 Turbulent combined oscillatory flow and current in a pipe. J. Fluid Mech. 373, 313–348.Google Scholar
Lohmann, I. P., Fredsøe, J., Sumer, B. M. & Christensen, E. D. 2006 Large eddy simulation of the ventilated wave boundary layer. J. Geophys. Res. 111, C06036, doi:10.1029/2005JC002946.Google Scholar
Lundgren, H. & Jonsson, I. G. 1961 Bed shear stress induced by a wave motion. Coastal Engineering Laboratory, Technical University of Denmark. Basic Research Progress Report, 1, 3–5.Google Scholar
Matsubara, M. & Alfredsson, P. H. 2001 Disturbance growth in boundary layers subjected to free-stream turbulence. J. Fluid Mech. 430, 149–168.Google Scholar
Orszag, S. A. & Patera, A. T. 1983 Secondary instability of wall-bounded shear flows. J. Fluid Mech. 128, 347–385.Google Scholar
Perry, A., Lim, T. & Teh, E. 1981 A visual study of turbulent spots. J. Fluid Mech. 104, 387–405.Google Scholar
Ramaprian, B. R. & Tu, S. W. 1980 An experimental study of oscillatory pipe flow at transitional Reynolds number. J. Fluid Mech. 100, 513–544.Google Scholar
Salon, S., Armenio, V. & Crise, A. 2007 A numerical investigation of the Stokes boundary layer in the turbulent regime. J. Fluid Mech. 570, 253–296.Google Scholar
Sarpkaya, T. 1966 Experimental determination of the critical Reynolds number for pulsating Pouseuille flow. Trans. ASME J. Basic Engng 88, 589–598.Google Scholar
Sarpkaya, T. 1993 Coherent structures in oscillatory boundary layers. J. Fluid Mech. 253, 105–140.Google Scholar
Schlichting, H. 1979 Boundary Layer Theory. McGraw-Hill.Google Scholar
Seifert, A. & Wygnanski, I. J. 1995 On turbulent spots in a laminar boundary layer subjected to a self-similar adverse pressure gradient. J. Fluid Mech. 296, 185–209.Google Scholar
Sleath, J. F. A. 1984 Sea Bed Mechanics. John Wiley & Sons.Google Scholar
Sleath, J. F. A. 1987 Turbulent oscillatory flow over rough beds. J. Fluid Mech. 182, 369–409.Google Scholar
Soulsby, R. L., Hamm, L., Klopman, G., Myrhaug, D., Simons, R. R. & Thomas, G. P. 1993 Wave-current interaction in the vertical. Coastal Engng 21, 41–69.Google Scholar
Spalart, P. R. & Baldwin, B. S. 1987 Direct simulation of a turbulent oscillating boundary layer. NASA Tech. Mem. 89460 Ames Research Center, Moffett Field, California.Google Scholar
Sumer, B. M. 2003 Experimental investigation of wave boundary layer. EUROMECH Colloquium No. 451, pp. 26–29. Taormina, Italy, General Lecture. PowerPoint presentation obtainable from the author ().Google Scholar
Sumer, B. M., Jensen, B. L. & Fredsøe, J. 1987 Turbulence in oscillatory boundary layers. In Advances in Turbulence (ed. Comte-Bello, Gt. & Mathieu, J.), pp. 556–567. Springer.Google Scholar
Tromans, P. S. 1978 Stability and transition of periodic pipe flows. PhD thesis, Cambridge University.Google Scholar
Tuzi, R. & Blondeaux, P. 2008 Intermittent turbulence in a pulsating pipe flow. J. Fluid Mech. 599, 51–79.Google Scholar
Vittori, G. & Verzicco, R. 1998 Direct simulation of transition in an oscillatory boundary layer. J. Fluid Mech. 371, 207–232.Google Scholar

Carstensen et al. supplementary movie 1

Movie 1. (Fig. 5) Time evolution of vortex tubves (plan view). Test 5, Half Cycle 5. Re = 2.9×105. ωt = 147 to 185 degrees. The flow near the bed (where the vortex tubes are located) is from right to left, and therefore the system of vortex tubes are in constant motion from right to left thorughout the sequence.

Download Carstensen et al. supplementary movie 1(Video)
Video 119.2 KB

Carstensen et al. supplementary movie 2

Movie 2. (Fig. 9) Video illustrating the time development of a turbulent spot. Test 6, Half Cycle 4. Re = 4.5×105. ωt = 50 to 200 degrees. Free-stream flow from right to left.

Download Carstensen et al. supplementary movie 2(Video)
Video 466.3 KB

Carstensen et al. supplementary movie 3

Movie 3. (N/A) Turbulent Spot (Side view). Test 10. Re = 3.3×105. Free-stream direction from left to right.

Download Carstensen et al. supplementary movie 3(Video)
Video 166.3 KB

Carstensen et al. supplementary movie 4

Movie 4. (Fig. 12) Turbulent spots and vortex tubes occur concurrently in space(plan view). Test 7, Half Cycle 3. Re = 3.0×105. ωt = 54 to 209 degrees. Free-stream direction from left to right.

Download Carstensen et al. supplementary movie 4(Video)
Video 465.7 KB