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This data is large eddy simulation model output of turbulent airflow over misaligned surfaces waves (up to 90 degrees) for strongly forced to weakly forced conditions (wave age up to 10.95) using a wave-following mapped coordinate, for the following manuscript: Manzella, E., Hara, T., Sullivan, P. Reduction of Drag Coefficient due to Misaligned Surface Waves. (Manuscript in preparation) From these data for wind aligned with waves (0 degrees) to wind misaligned with waves (22.5, 45, 67.5, 90 degrees) and wave age (c/u*=1.37, 5.48, 10.95) with corresponding variable names (1x, 4x, 8x) we look at equivalent roughness length and wave growth/decay variables. In addition to the cross-wave component of the velocity (v), we also include the rotated along-wind (U) and cross-wind (V) variables. We look at horizontally averaged vertical profiles of the following: -Wind speed, wind shear, wind speed angle, and wind shear angle -Turbulent kinetic energy -Energy budget (including shear production, transport, and viscous dissipation) -Momentum budget (including pressure stress, turbulent stress, and wave-coherent stress) We also look at phase-averaged flow fields of the following: -Wind speed (horizontal and vertical) -Pressure -Turbulent kinetic energy -Dissipation rate -Vorticity (cross-wind) -Turbulent and wave-coherent stress -Pressure, turbulent tangential stress, and turbulent normal stresses (surface distribution) Finally, we look at cross-wind turbulent instantaneous vorticity fields for the 0 and 90 degrees for the lowest and highest wave ages
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Reduction of Drag Coefficient Due To Misaligned Wind‐Waves
Abstract Recent field observations suggest that the air‐sea momentum flux (or the drag coefficient) is significantly reduced when the dominant wind‐forced surface waves are misaligned from local wind. Such conditions may occur under rapidly changing strong winds (such as under tropical cyclones) or in coastal shallow waters where waves are refracted by bottom topography. A recent Large Eddy Simulation (LES) study also shows that the drag coefficient is reduced by a misaligned strongly forced wave train (with a small wave age of 1.37). In order to investigate more realistic field conditions, this study employs LES to examine the effect of a misaligned (up to 90°) surface wave train over a wide range of wave age up to 10.95. For all wave ages examined, the drag coefficient is reduced compared to the flat surface condition when the misalignment angle exceeds around 22.5°–45°. The drag reduction may occur even if the form drag of the wave train is positive.
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- Award ID(s):
- 2048752
- PAR ID:
- 10574054
- Publisher / Repository:
- American Geophysical Union
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Oceans
- Volume:
- 129
- Issue:
- 5
- ISSN:
- 2169-9275
- Format(s):
- Medium: X
- Associated Dataset(s):
- View Associated Dataset(s) >>
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2023JC020593
