Tag: Breaking Waves

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Research Papers and Reports

Langmuir Circulations and Meandering Flows

Windrows

The Ocean’s Heartbeat

Electric and Magnetic Fields of Meandering Flows

  • Dommermuth, D. G., “Magnetic Induction due to the Effects of Breaking Ocean Waves,” ResearchGate preprint, Oct 2020.
    https://www.researchgate.net/publication/344482876
  • Dommermuth, D. G., “The Generation of Electric Fields by Meandering Flows,” ResearchGate preprint, Oct 2020. https://www.researchgate.net/publication/344787449 (Please see more recent technical reports on the electric field that is induced by the transport of space charge density by the meandering wind.)
  • Dommermuth, D. G., “The Electric and Magnetic Fields due to the Transport of Space Charge Density by the Meandering Wind over the Ocean Surface,” ResearchGate preprint, Sep 2021. https://www.researchgate.net/publication/354665883 (Please see more recent technical reports on the electric field that is induced by the transport of space charge density by the meandering wind.)
  • Dommermuth, D.G., “The Electric and Magnetic Fields due to the Transport of Space Charge Density by the Meandering Wind over the Ocean Surface: New Evidence of an Inverse Energy Cascade in the Lower Atmosphere,” ResearchGate preprint, Sep 2021. https://www.researchgate.net/publication/354935485
  • Dommermuth, D.G., “The Electric and Magnetic Fields due to Magnetic Induction by Meandering Flows in the Oceanic and Atmospheric Boundary Layers: New Evidence of an Inverse Energy Cascade in the Upper Ocean,” ResearchGate preprint, Oct 2021. https://www.researchgate.net/publication/355215804
  • Dommermuth, D.G., “The Magnetic Fields due to Magnetic Induction by Meandering Drift Currents,” ResearchGate preprint, Oct 2021. https://www.researchgate.net/publication/355651651
  • Dommermuth, D.G., “A Parametric Study of the Electric Field in the Atmosphere due to the Transport of Space Charge Density by the Meandering Wind over the Ocean Surface,” ResearchGate preprint, Nov 2021. https://www.researchgate.net/publication/356002487

Maxima Scripts for Meandering Flows

  • Dommermuth, D.G., “Maxima Coding for Solving the Electric and Magnetic Fields due to the Transport of Space Charge Density over the Ocean Surface: New Evidence of an Inverse Energy Cascade in the Lower Atmosphere,” ResearchGate code, Sep 2021. https://www.researchgate.net/publication/354935522
  • Dommermuth, D.G., “A Maxima Script for Solving the Electric and Magnetic Fields due to Magnetic Induction by Meandering Flows in the Oceanic and Atmospheric Boundary Layers: New Evidence of an Inverse Energy Cascade in the Upper Ocean,” ResearchGate code, Oct 2021. https://www.researchgate.net/publication/355209396

Fortran Codes for Meandering Flows

  • Dommermuth, D.G., “A Fortran Code for Calculating Electric and Magnetic Fields due to the Transport of Space Charge Density by the Meandering Wind over the Ocean Surface: New Evidence of an Inverse Energy Cascade in the Lower Atmosphere,” ResearchGate code, Sep 2021. https://www.researchgate.net/publication/354935467
  • Dommermuth, D.G., “A Fortran Code for Calculating the Electric and Magnetic Fields due to Magnetic Induction by Meandering Flows in the Oceanic and Atmospheric Boundary Layers: New Evidence of an Inverse Energy Cascade in the Upper Ocean,” ResearchGate code, Oct 2021. https://www.researchgate.net/publication/355209298
  • Dommermuth, D.G., “F90 Coding for Calculating the Magnetic Fields due to Magnetic Induction by Meandering Drift Currents,” ResearchGate code, Oct 2021. https://www.researchgate.net/publication/355651566
  • Dommermuth, D.G., “F90 Coding for a Parametric Study of the Electric Field in the Atmosphere due to the Transport of Space Charge Density by the Meandering Wind over the Ocean Surface,” ResearchGate code, Nov 2021. https://www.researchgate.net/publication/356002311

The Effect of the Wind Drift on Wave Growth, Wave Breaking, and the Production of Turbulence

The Effect of Standing Waves on the Wave Energy Cascade

Helmholtz Decompositions into Wavy and Vortical Portions

  • Dommermuth, D. G., “The laminar interactions of a pair of vortex tubes with a free surface,” J. Fluid Mech., Vol. 246, 1993, pp. 91–115. https://doi.org/10.1017/S0022112093000059
  • Mui, R. C. and Dommermuth, D. G., “The vortical structure of a near-breaking gravity-capillary wave,” Journal of Fluids Engineering, Vol. 117, 1994,355–361. https://doi.org/10.1115/1.2817269
  • Dommermuth, D. G., Novikov, E.A., and Mui, C.Y., “The Interaction of Surface Waves with Turbulence,” The Proceedings of the Symposium on Free-Surface Turbulence, ASME Fluids Engineering Division Summer Meeting, Lake Tahoe, California, USA, 1994. https://www.researchgate.net/publication/271527603

Entrainment and Mixing due to Plunging Breaking Waves

Numerical Methods

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Windrows

https://www.researchgate.net/publication/344943225

Dommermuth et al. (2014); Dommermuth (2020b) show that windrows form due to the action of breaking waves. Foam, biological material, flotsam, and jetsam surf the fronts of breaking waves. The surfing action of the breaking waves scrubs the free surface clean like a wedge plow on a train clears snow. Dommermuth et al. (2014); Dommermuth (2020b) hypothesize that each successive pass of a breaking wave increases the length of the windrows. There is a sweet spot for forming long rectilinear windrows whereby there is surfing followed by spilling of foam, flotsam, jetsam, etc. off to the sides of the whitecaps. Dommermuth (2020c) shows that windrows are less likely to persist if the whitecaps are long crested. When whitecaps are too long transverse to the wind, successive passes of breaking waves tend to break up the windrows. Conversely, if whitecaps are too narrow transverse to the wind, there is no surfing to line up foam, flotsam, jetsam, etc. Here, numerical simulations confirm that successive surfing and scrubbing events lead to the formation of windrows. For Type 1 Windrows, successive spilling breaking waves progress down the middle of the breaking wave that proceeded them, whereas for Type 2 Windrows, successive spilling breaking waves progress down the middle of the windrow band of the breaking wave that proceeded them. The windrows that are formed by Type 1 interactions are thick and rectilinear. The windrows that are formed by Type 2 interactions are thinner, clumpy, and serpentine. Type 2 Windrows have twice as many bands as Type 1. Random fluctuations to the lateral positions of the spilling breakers show that Type 1 and Type 2 Windrows are persistent over a broad range. However, windrows will not form if the lateral positions of spilling breaking waves are uniformly distributed relative to each other.

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Further Observations on how Wave Breaking Affects the Formation of Windrows

https://www.researchgate.net/publication/344482865

Dommermuth et al. (2014) shows that windrows form due to the action of breaking waves. Foam, biological material, flotsam, and jetsam surf the fronts of breaking waves. The surfing action of the breaking waves scrubs the free surface clean like a wedge plow on a train clears snow. Each successive pass of a breaking wave increases the length of the windrows. This surfing mechanism differs from Langmuir (1938)’s original hypothesis that the “seaweed accumulated in streaks because of transverse surface currents converging toward the streaks.” There is a sweet spot for forming long rectilinear windrows whereby there is surfing followed by spilling of foam, flotsam, jetsam, etc. off to the sides of the whitecaps. Windrows are less likely to persist if the whitecaps are long crested. When whitecaps are too long transverse to the wind, successive passes of breaking waves tend to break up the windrows. Conversely, if whitecaps are too narrow transverse to the wind, there is no surfing to line up foam, flotsam, jetsam, etc.

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The Entrainment and Mixing of Air due to a Rectilinear Vortex Moving Parallel to a Free Surface

https://www.researchgate.net/publication/342247893

A rectilinear vortex with a core filled with air models a plunging breaking wave whose tip has pinched off a pocket of air. For a rectilinear vortex moving parallel to the free surface, air is entrained as the free surface wraps around the axial vorticity. The amount of air that is entrained depends on a Froude number that is based on the circulation of vorticity. Cross-axis vorticity is formed as a result of instabilities in the axial vorticity. Roll-wave instabilities form on the outer face of the sheet of water that wraps around the axial vorticity. For sufficiently high Froude numbers, both the axial and cross-axis vortex tubes entrain air. The air that is entrained is driven by pressure gradients toward the centers of the axial and cross-axis vortex tubes where the pressures are minimal.