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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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Boundary layer formulations in orthogonal curvilinear coordinates for flow over wind-generated surface waves
The development of the governing equations for fluid flow in a surface-following coordinate system is essential to investigate the fluid flow near an interface deformed by propagating waves. In this paper, the governing equations of fluid flow, including conservation of mass, momentum and energy balance, are derived in an orthogonal curvilinear coordinate system relevant to surface water waves. All equations are further decomposed to extract mean, wave-induced and turbulent components. The complete transformed equations include explicit extra geometric terms. For example, turbulent stress and production terms include the effects of coordinate curvature on the structure of fluid flow. Furthermore, the governing equations of motion were further simplified by considering the flow over periodic quasi-linear surface waves wherein the wavelength of the disturbance is large compared to the wave amplitude. The quasi-linear analysis is employed to express the boundary layer equations in the orthogonal wave-following curvilinear coordinates with the corresponding decomposed equations for the mean, wave and turbulent fields. Finally, the vorticity equations are also derived in the orthogonal curvilinear coordinates in order to express the corresponding velocity–vorticity formulations. The equations developed in this paper proved to be useful in the analysis and interpretation of experimental data of fluid flow over wind-generated surface waves. Experimental results are presented in a companion paper.
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- Award ID(s):
- 1634051
- PAR ID:
- 10208693
- Date Published:
- Journal Name:
- Journal of fluid mechanics
- Volume:
- 888
- Issue:
- A11
- ISSN:
- 1469-7645
- Format(s):
- Medium: X
- 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/10.1017/jfm.2020.32
