Abstract
Oceanic turbulence plays an important role in coastal flow. However, as the effect of an uneven lower boundary on the adjacent turbulence is still not well understood, we explore the mechanics of nearshore turbulence with a turbulence-resolving numerical model known as a large-eddy-simulation model for an idealized scenario in a coastal region for which the lower boundary is a solid sinusoidal wave. The numerical simulation demonstrates how the mechanical energy of the current is transferred into local turbulence mixing, and shows the changes in turbulent intensity over the continuous phase change of the lower topography. The strongest turbulent kinetic energy is concentrated above the trough of the wavy surface. The turbulence mixing is mainly generated by the shear forces; the magnitude of shear production has a local maximum over the crest of the seabed topography, and there is an asymmetry in the shear production between the leeward and windward slopes. The numerical results are consistent with results from laboratory experiments. Our analysis provides an important insight into the mechanism of turbulent kinetic energy production and development.
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References
Broglia R, Pascarelli A, Piomelli U. 2003. Large-eddy simulations of ducts with a free surface. Journal of Fluid Mechanics, 484: 223–253.
Calhoun R J, Street R L. 2001. Turbulent flow over a wavy surface: neutral case. Journal of Geophysical Research: Oceans, 106 (C5): 9 277–9 293.
Chang Y S, Scotti A. 2004. Modeling unsteady turbulent flows over ripples: Reynolds-averaged Navier-Stokes equations (RANS) versus large-eddy simulation (LES). Journal of Geophysical Research: Oceans, 109 (C9): C09012.
Grigoriadis D G E, Balaras E, Dimas A A. 2013. Coherent structures in oscillating turbulent boundary layers over a fixed rippled bed. Flow, Turbulence and Combustion, 91 (3): 565–585.
Grigoriadis D G E, Dimas A A, Balaras E. 2012. Large-eddy simulation of wave turbulent boundary layer over rippled bed. Coastal Engineering, 60: 174–189.
Harris J C, Grilli S T. 2012. A perturbation approach to large eddy simulation of wave-induced bottom boundary layer flows. International Journal for Numerical Methods in Fluids, 68 (12): 1 574–1 604.
Henn D S, Sykes R I. 1999. Large-eddy simulation of flow over wavy surfaces. Journal of Fluid Mechanics, 383: 75–112.
Jackett D R, McDougall T J, Feistel R et al. 2006. Algorithms for density, potential temperature, conservative temperature, and the freezing temperature of seawater. Journal of Atmospheric and Oceanic Technology, 23 (12): 1 706–1 728.
Jackson P S, Hunt J C R. 1975. Turbulent wind flow over a low hill. Quarterly Journal of the Royal Meteorological Society, 101 (430): 929–955.
Kantha L H, Clayson C A. 2004. On the effect of surface gravity waves on mixing in the oceanic mixed layer. Ocean Modelling, 6 (2): 101–124.
Large W G, Gent P R. 1999. Validation of vertical mixing in an equatorial ocean model using large eddy simulations and observations. Journal of Physical Oceanography, 29 (3): 449–464.
Large W G, McWilliams J C, Doney S C. 1994. Oceanic vertical mixing: a review and a model with a nonlocal boundary layer parameterization. Reviews of Geophysics, 32 (4): 363–403.
Li M, Zhong L J, Boicourt W C. 2005. Simulations of Chesapeake Bay estuary: sensitivity to turbulence mixing parameterizations and comparison with observations. Journal of Geophysical Research: Oceans, 110 (C12): C12004.
Li S, Song J B, He H L et al. 2013. Large eddy simulation of turbulence in ocean surface boundary layer at Zhangzi Island offshore. Acta Oceanologica Sinica, 32 (7): 8–13.
Li Y J, Chen J B, Zhou J F et al. 2016. Large eddy simulation of boundary layer flow under cnoidal waves. Acta Mechanica Sinica, 32 (1): 22–37.
Maronga B, Gryschka M, Heinze R et al. 2015. The Parallelized Large-Eddy Simulation Model (PALM) version 4.0 for atmospheric and oceanic flows: model formulation, recent developments, and future perspectives. Geoscientific Model Development, 8 (8): 2 515–2 551.
McWilliams J C, Sullivan P P. 2000. Vertical mixing by Langmuir circulations. Spill Science & Technology Bulletin, 6 (3–4): 225–237.
Mellor G L, Yamada T. 1982. Development of a turbulence closure model for geophysical fluid problems. Reviews of Geophysics, 20 (4): 851–875.
Moeng C H, Wyngaard J C. 1988. Spectral analysis of largeeddy simulations of the convective boundary layer. Journal of the Atmospheric Sciences, 45 (23): 3 573–3 587.
Poggi D, Katul G G, Albertson J D et al. 2007. An experimental investigation of turbulent flows over a hilly surface. Physics of Fluids, 19 (3): 036601.
Saiki E M, Moeng C H, Sullivan P P. 2000. Large-eddy simulation of the stably stratified planetary boundary layer. Boundary-Layer Meteorology, 95 (1): 1–30.
Smyth W D, Skyllingstad E D, Crawford G B et al. 2002. Nonlocal fluxes and Stokes drift effects in the K-profile parameterization. Ocean Dynamics, 52 (3): 104–115.
Soldati A, Marchioli C. 2012. Sediment transport in steady turbulent boundary layers: potentials, limitations, and perspectives for Lagrangian tracking in DNS and LES. Advances in Water Resources, 48: 18–30.
Umlauf L, Burchard H. 2003. A generic length-scale equation for geophysical turbulence models. Journal of Marine Research, 61 (2): 235–265.
Walker R, Tejada-Martínez A E, Grosch C E. 2016. Largeeddy simulation of a coastal ocean under the combined effects of surface heat fluxes and full-depth Langmuir circulation. Journal of Physical Oceanography, 46 (8): 2 411–2 436, https://doi.org/10.1175/JPO-D-15-0168.1.
Wijesekera H W, Allen J S, Newberger P A. 2003. Modeling study of turbulent mixing over the continental shelf: comparison of turbulent closure schemes. Journal of Geophysical Research: Oceans, 108 (C3): 3103.
Wilcox D C. 1988. Reassessment of the scale-determining equation for advanced turbulence models. AIAA Journal, 26 (11): 1 299–1 310.
Wu J. 1980. Wind-Stress coefficients over sea surface near Neutral Conditions—a revisit. Journal of Physical Oceanography, 10 (5): 727–740.
Zeng J, Constantinescu G, Blanckaert K et al. 2008. Flow and bathymetry in sharp open-channel bends: experiments and predictions. Water Resources Research, 44 (9): W09401.
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We thank the two anonymous reviewers for their constructive comments.
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Supported by the National Key Research and Development Program of China (Nos. 2016YFC1401404, 2017YFA0604102), the National Natural Science Foundation of China (Nos. 41506015, 41576013), the Zhejiang Provincial Natural Science Foundation (No. LY16D060001), and the Open Research Fund of the State Key Laboratory of Estuarine and Coastal Research (No. SKLEC-KF201406)
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Lu, Z., Fan, W., Li, S. et al. Large-eddy simulation of the influence of a wavy lower boundary on the turbulence kinetic energy budget redistribution. J. Ocean. Limnol. 36, 1178–1188 (2018). https://doi.org/10.1007/s00343-018-7015-y
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DOI: https://doi.org/10.1007/s00343-018-7015-y