Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow
The theory of surface wave generation, in viscous flows, is modified by replacing the linear-logarithmic shear velocity profile, in the air, with a model which links smoothly the linear and logarithmic layers through the buffer layer. This profile includes the effects of air flow turbulence using a...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-01-01
|
| Series: | Journal of Marine Science and Engineering |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2077-1312/10/1/46 |
| _version_ | 1797492881459511296 |
|---|---|
| author | Malek Abid Christian Kharif Hung-Chu Hsu Yang-Yih Chen |
| author_facet | Malek Abid Christian Kharif Hung-Chu Hsu Yang-Yih Chen |
| author_sort | Malek Abid |
| collection | DOAJ |
| description | The theory of surface wave generation, in viscous flows, is modified by replacing the linear-logarithmic shear velocity profile, in the air, with a model which links smoothly the linear and logarithmic layers through the buffer layer. This profile includes the effects of air flow turbulence using a damped mixing-length model. In the water, an exponential shear velocity profile is used. It is shown that this modified and coupled shear-velocity profile gives a better agreement with experimental data than the coupled linear-logarithmic, non smooth profile, (in the air)–exponential profile (in the water), widely used in the literature. We also give new insights on retrograde modes that are Doppler shifted by the surface velocity at the air-sea interface, namely on the threshold value of the surface current for the occurrence of a second unstable mode. |
| first_indexed | 2024-03-10T01:11:59Z |
| format | Article |
| id | doaj.art-2ead364f57b4456fae4edf05f4f294f0 |
| institution | Directory Open Access Journal |
| issn | 2077-1312 |
| language | English |
| last_indexed | 2024-03-10T01:11:59Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Marine Science and Engineering |
| spelling | doaj.art-2ead364f57b4456fae4edf05f4f294f02023-11-23T14:16:07ZengMDPI AGJournal of Marine Science and Engineering2077-13122022-01-011014610.3390/jmse10010046Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-FlowMalek Abid0Christian Kharif1Hung-Chu Hsu2Yang-Yih Chen3École Centrale de Marseille, Aix Marseille Université, CNRS, IRPHE UMR 7342, 13384 Marseille, FranceÉcole Centrale de Marseille, Aix Marseille Université, CNRS, IRPHE UMR 7342, 13384 Marseille, FranceDepartment of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung 80424, TaiwanDepartment of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung 80424, TaiwanThe theory of surface wave generation, in viscous flows, is modified by replacing the linear-logarithmic shear velocity profile, in the air, with a model which links smoothly the linear and logarithmic layers through the buffer layer. This profile includes the effects of air flow turbulence using a damped mixing-length model. In the water, an exponential shear velocity profile is used. It is shown that this modified and coupled shear-velocity profile gives a better agreement with experimental data than the coupled linear-logarithmic, non smooth profile, (in the air)–exponential profile (in the water), widely used in the literature. We also give new insights on retrograde modes that are Doppler shifted by the surface velocity at the air-sea interface, namely on the threshold value of the surface current for the occurrence of a second unstable mode.https://www.mdpi.com/2077-1312/10/1/46Orr-Sommerfeld equationwind wavesgravitycapillarityshear flowsinstability |
| spellingShingle | Malek Abid Christian Kharif Hung-Chu Hsu Yang-Yih Chen Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow Journal of Marine Science and Engineering Orr-Sommerfeld equation wind waves gravity capillarity shear flows instability |
| title | Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow |
| title_full | Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow |
| title_fullStr | Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow |
| title_full_unstemmed | Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow |
| title_short | Generation of Gravity-Capillary Wind Waves by Instability of a Coupled Shear-Flow |
| title_sort | generation of gravity capillary wind waves by instability of a coupled shear flow |
| topic | Orr-Sommerfeld equation wind waves gravity capillarity shear flows instability |
| url | https://www.mdpi.com/2077-1312/10/1/46 |
| work_keys_str_mv | AT malekabid generationofgravitycapillarywindwavesbyinstabilityofacoupledshearflow AT christiankharif generationofgravitycapillarywindwavesbyinstabilityofacoupledshearflow AT hungchuhsu generationofgravitycapillarywindwavesbyinstabilityofacoupledshearflow AT yangyihchen generationofgravitycapillarywindwavesbyinstabilityofacoupledshearflow |