Abstract
It is generally recognized that large-scale turbulent coherent structures play an important role in the transport of sediment and contaminants in rivers. They are also believed to be related to the origin and development of a variety of fluvial bed and plan forms. While intensive laboratory and field research has been devoted in recent years to the study of large-scale vertical coherent structures, no such efforts have yet been directed to the study of large-scale horizontal coherent structures. This paper is intended as a contribution to address the existing lack of information on the latter structures. Its objective is to report an application of continuous wavelet transform (CWT) to the detection and establishment of the length and time scales of the largest coherent structures existing in a shallow open channel flow (width to depth ratio equal to 25), focusing primarily on the horizontal structures. The analysis is based on measurements of instantaneous flow velocity previously carried out in a 21 m long, 1 m wide flume. These include 306 single point velocity measurements collected throughout the flow field at a constant distance from the bed surface, the duration of each measurement being 120 s; and 20 min long measurements carried out at selected locations. The velocity was measured with the aid of a 2D Micro Acoustic Doppler Velocity meter. Large-scale horizontal coherent structures could be identified in all of the velocity records, and appeared as quasi-cyclic, sustained features in the flow. The intervals of time where such structures could not be detected were invariably short in comparison to the measurement time. CWT was found to be particularly well suited to determine the average time and length scales of the structures, two quantities of special significance in river morphodynamics. The average time scale of the large-scale horizontal structures for the investigated flow was found to be equal to 22.3 s, which implies a length scale of five times the flow width. Individual horizontal coherent structures with characteristic times approximately twice larger than the value of average time scale could be identified in the flow. However, these were infrequent occurrences in the flow.
Similar content being viewed by others
References
Adrian RJ, Marusic I (2012) Coherent structures in flow over hydraulic engineering surfaces. J Hydraul Res 50(5):451–464
Ahmari H (2010) Size, dynamics and consequences of large-scale horizontal coherent structures in open-channel flows: an experimental study. Ph.D. Thesis, Queen’s University, Kingston
Ahmari H, da Silva AMF (2011) Region of bars, meandering and braiding in da Silva and Yalin’s plan. J Hydraul Res 49(6):718–727
Anderson W, Chamecki M (2014) Numerical study of turbulent flow over complex aeolian dune fields: The White Sands National Monument. Phys Rev E. doi:10.1103/PhysRevE.89.013005
Auto Signal Version 1.7. (2003) User’s Manual, ISBN 81-88341-08-8. Seasolve, Richmond
Best J (2005) The fluid dynamics of river dunes: a review and some future research directions. J Geophys Res: Earth Surf (20032012) 110(F4)
Blanckaert K, Constantinescu G, Uijttewaal W, Chen Q (2013) Hydro-and morphodynamics in curved river reaches: recent results and directions for future research. Adv Geosci 37(37):19–25
Bonnet JP, Delville J (1996) General concepts on structure identification. In: Eddy structure identification. Springer, Vienna, pp 1–59
Breugem WA, Uijttewaal WSJ (2007) Sediment transport by coherent structures in a turbulent open channel flow experiment. Particle-Laden flow. Springer, Netherlands, pp 43–55
Camussi R (2002) Coherent structure identification from wavelet analysis of particle image velocimetry data. Exp Fluids 32(1):76–86
Cellino M, Lemmin U (2004) Influence of coherent flow structures on the dynamics of suspended sediment transport in open-channel flow. J Hydraul Eng 130(11):1077–1088
Chang K, Constantinescu G (2013) Coherent structures in flow over two-dimensional dunes. Water Resour Res 49(5):2446–2460
Constantinescu G, Miyawaki S, Rhoads B, Sukhodolov A (2012) Numerical analysis of the effect of momentum ratio on the dynamics and sediment entrainment capacity of coherent flow structures at a stream confluence. J Geophys Res: Earth Surf 117(F4)
da Silva AMF (1991) Alternate bars and related alluvial processes. M.Sc. Thesis, Queen’s University, Kingston
da Silva AMF (2006) On why and how do rivers meander. J Hydraul Res 44(5):579–590
da Silva AMF, El-Tahawy T (2008) On the location in flow plan of erosion-deposition zones in sine-generated meandering streams. J Hydraul Res 46(Extra Issue 1):49–60
da Silva AMF, Ahmari H (2009) Size and effect on the mean flow of large-scale horizontal coherent structures in open-channel flows: an experimental study. Special Issue in Honour of Professor M. Selim Yalin (1925–2007). Can J Civ Eng 36(10):1643–1655
da Silva AMF, Ahmari H, Kanani A (2012) Characteristic scales and consequences of large-scale horizontal coherent structures in open-channel flows. In: Rodi W, Markus U (eds) Environmental fluid mechanics: memorial volume in honour of Prof. Gerhard H. Jirka. IAHR Monograph Series, CRC Press, Boca Raton, pp 85–105
del Álamo JC, Jiménez J (2003) Spectra of the very large anisotropic scales in turbulent channels. Phys Fluids 15(6):L41–L44
Escauriaza C, Gonzalez C, Guerra P, Pasten P, Pizarro G (2012) Formation and fate of contaminant particles controlled by turbulent coherent structures and geochemistry in a reactive river confluence. Bull Am Phys Soc 57(17) BAPS.2012.DFD.A13.5
Farge M (1992) Wavelet transforms and their applications to turbulence. Annu Rev Fluid Mech 24:395–447
Farge M, Guezennec Y, Ho CM, Meneveau C (1990) Continuous wavelets analysis of coherent structures. In: Proceedings of the Summer Program (1990). Center for Turbulence Research. Stanford University NASA-Ames, Stanford
Farge M, Schneider K (2001) Analysising and computing turbulent flows using wavelets. In: Lesieur M, Yaglom AM, David F (eds) New trends in turbulence. Springer, Berlin
Franca MJ, Lemmin U (2015) Detection and reconstruction of large-scale coherent flow structures in gravel-bed rivers. Earth Surf Process Landf 40:93–104
Franca MJ, Lemmin U (2006) Detection and reconstruction of coherent structures based on wavelet multiresolution analysis. In: Proceedings of River Flow 2006, 3rd international conference on fluvial hydraulics, Lisbon, Portugal, Sept. 6–8, 2006, Ferreira, Alves, Leal & Cardoso (eds), Taylor & Francis Group, London, pp 181–190
Franca MJ (2005) A field study of turbulent flows in shallow gravel-bed rivers. Ph.D. Dissertation, École Polytechnique Fédérale de Lausanne (EPFL). doi: 10.5075/epfl-thesis-3393
Gao RX, Yan R (2011) From Fourier transform to wavelet transform: a historical perspective. In: Wavelets. Springer, New York, pp 17–32
Grishanin KV (1979) Dynamics of alluvial streams. Gidrometeoizdat, Leningrad (In Russian)
Gutierrez RR, Abad JD (2014) On the analysis of the medium term planform dynamics of meandering rivers. Water Resour Res 50(5):3714–3733
Hayashi S, Ohmoto T (2002) Study on coherent vortex structures over sand ridges in an open channel flow by DNS. In: Proceedings of the hydraulic measurements and experimental methods (2002)(40655), 116: 1–10
Hussain AF (1983) Coherent structures—reality and myth. Phys Fluids 26(10):2816–2850
Hutchins N, Marusic I (2007) Evidence of very long meandering features in the logarithmic region of turbulent boundary layers. J Fluid Mech 579:1–28
Jackson G (1976) Sedimentological and fluid-dynamic implications of the turbulent bursting phenomenon in geophysical flows. J Fluid Mech 77:531–560
Kamphuis JW (1974) Determination of sand roughness for fixed beds. J Hydraul Res 12(2):193–203
Kanani A, Ahmari H, da Silva AMF (2010) Investigation of horizontal coherent structures in a shallow open-channel flow using velocity signal decomposition. In: Proceedings of the 5th international conference on fluvial hydraulics, river flow 2010, Braunschweig, pp 1059–1066
Khosronejad A, Sotiropoulos F (2014) Numerical simulation of sand waves in a turbulent open channel flow. J Fluid Mech 753:150–216
Kitagawa T, Nomura T (2003) A wavelet-based method to generate artificial wind fluctuation data. J Wind Eng Ind Aerodyn 91(7):943–964
Konsoer KM, Rhoads BL (2011) Spatial-temporal structure of mixing interface turbulence at two large river confluences. Environmental Fluid Mechanics, Springer, New York. doi:10.1007/s10652-013-9304-5
Kumar P, Foufoula-Georgiou E (1997) Wavelet analysis for geophysical applications. Rev Geophys 35(4):385–412
Lee J, Suh J, Sung HJ, Pettersen B (2012) Structures of turbulent open-channel flow in the presence of an airwater interface. J Turbul 13(18):1–18
Massel SR (2001) Wavelet analysis for processing of ocean surface wave records. Ocean Eng 28(8):957–987
McLean SR, Nelson JM, Wolfe SR (1994) Turbulence structure over two-dimensional bed forms: implications for sediment transport. J Geophys Res: Oceans (19782012) 99(C6):12729–12747
McLelland SJ, Ashworth P, Best JL (1996) The origin and downstream development of coherent flow structures at channel junctions. Coherent flow structures in open channels. Wiley, Chichester, pp 459–490
Miyamoto H, Kanda T (2004) Extraction of coherent structure from PIV data using wavelet transform. In: Proceedings of building partnerships, joint conference on water resource engineering and water resources planning & management 2000. ASCE. doi: 10.1061/40517(2000)326
Moser R, Kim J, Mansour NN (1999) Direct numerical simulation of turbulent channel flow up to Re\(_{r}\)= 590. Phys Fluids 11(4):943–945
Mwale D, Gan TY, Devito KJ, Silins U, Mendoza C, Petrone R (2010) Regionalization of runoff variability of Alberta, Canada, by wavelet, independent component, empirical orthogonal function, and geographical information system analyses. J Hydrol Eng 16(2):93–107
Najmi A-H, Sadowsky J (1997) The continuous wavelet transform and variable resolution time-frequency analysis. Johns Hopkins Appl Res Tech Dig 18(1):134–140
Nelson JM, McLean SR, Wolfe SR (1993) Mean flow and turbulence fields over two-dimensional bed forms. Water Resour Res 29(12):3935–3953
Nezu I, Nakagawa H (1993) Turbulence in open channels. AA Balkema, Rotterdam
Omidyeganeh M, Piomelli U (2013) Large-eddy simulation of three-dimensional dunes in a steady, unidirectional flow. Part 2. Flow structures. J Fluid Mech 734:509–534
Polikar R (1999) The story of wavelets. Phys Mod Topics Mech Electr Eng, pp 192–197
Pope SB (2000) Turbulent flows. Cambridge University Press, Cambridge
Robinson SK (1991) Coherent motions in the turbulent boundary layer. Annu Rev Fluid Mech 23:601–639
Rodi W, Constantinescu G, Stoesser T (2013) Large Eddy simulation in hydraulics. IAHR monograph. Taylor & Francis Group, Boca Raton
Roy AG, Buffin-Bélanger T, Lamarre H, Kirkbride AD (2004) Size, shape and dynamics of large-scale turbulent flow structures in a gravel-bed river. J Fluid Mech 500:1–27
Saggio A, Imberger J (1998) Internal wave weather in a stratified lake. Limnol Occeanogr 43(8):1780–1795
Smith CR, Metzler SP (1983) The characteristics of low-speed streaks in the near-wall region of a turbulent boundary layer. J Fluid Mech 129:27–54
Stoesser T, Braun C, Garcia-Villalba M, Rodi W (2008) Turbulence structures in flow over two-dimensional dunes. J Hydraul Eng 134(1):42–55
Sukhodolov AN, Uijttewaal WS (2010) Assessment of a river reach for environmental fluid dynamics studies. J Hydraul Eng 136(11):880–888
Sukhodolov AN, Nikora VI, Katolikov VM (2011) Flow dynamics in alluvial channels: the legacy of Kirill V. Grishanin. J Hydraul Res 49(3):285–292
Sullivan P, Pollard A (1996) Coherent structure identification from the analysis of hot-wire data. Meas Sci Technol 7(10):1498–1516
Sumer BM, Chua LH, Cheng NS, Fredsøe J (2003) Influence of turbulence on bed load sediment transport. J Hydraul Eng 129(8):585–596
Torrence C, Compo PG (1998) A practical guide to wavelet analysis. Bull Am Meteorol Soc 79(1):61–78
Xie Z, Lin B, Falconer RA (2014) Turbulence characteristics in free-surface flow over two-dimensional dunes. J Hydro-environment Res, pp 1–10
Yalin MS (1977) Mechanics of sediment transport, 2nd edn. Pergamon Press, Oxford
Yalin MS (1992) River mechanics. Pergamon Press, Oxford
Yalin MS, da Silva AMF (2001) Fluvial processes. IAHR monograph. IAHR, Delft
Yokosi S (1967) The structure of river turbulence. Bull Disaster Prev Res Inst, Kyoto Univ, 17(121). Part 2:1–29
Yuan YM, Mokhtarzadeh-Dehghan MR (1999) Parameter effects on detection of coherent structures in turbulent boundary layers using conditional sampling methods. Fluid Dyn Res 25(2):87–112
Acknowledgments
This research was supported by funds from the Natural Sciences and Engineering Research Council of Canada, through a Discovery Grant to the second author, as well as funds from the Ontario Research and Development Challenge Fund. The authors are grateful to two anonymous reviewers whose comments and suggestions were of great help to develop the paper to its present form.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Kanani, A., Ferreira da Silva, A. Application of continuous wavelet transform to the study of large-scale coherent structures. Environ Fluid Mech 15, 1293–1319 (2015). https://doi.org/10.1007/s10652-015-9428-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10652-015-9428-x