Langmuir circulations and enhanced turbulence beneath wind-waves
Autor: | Moacyr Araujo, Denis Dartus, Lucien Masbernat, Philippe Maurel |
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Rok vydání: | 2001 |
Předmět: |
Physics
Atmospheric Science Turbulence K-epsilon turbulence model Wind stress Thermodynamics Mechanics K-omega turbulence model Geotechnical Engineering and Engineering Geology Oceanography Momentum Physics::Space Physics Wind wave Turbulence kinetic energy Computer Science (miscellaneous) Boundary value problem |
Zdroj: | Ocean Modelling. 3:109-126 |
ISSN: | 1463-5003 |
Popis: | This paper presents a set of experiments which describes the mutual influences between wind-wave enhanced turbulence and secondary motions like Langmuir circulations (LCs). Different external driven forces were produced in laboratory wind-wave flumes, and mean and turbulent fields were measured for each experimental situation. A (k–e) model coupled to momentum equations are numerically integrated to investigate the influences of a diffusion–dissipation (Diff=e) equilibrium of turbulent kinetic energy (TKE) to represent surface boundary conditions under wind-waves. A new formulation for estimating surface energy is obtained from wave and wind stress parameters, expressed in non-dimensional grounds as k S =0.12(σa/u ∗ ) 2 +C μ −1/2 . The close fit between measurements and numerical results suggests that Craik–Leibovich's equations associated with (k–e) turbulence model provides a good description of flow characteristics. Model issues confirm that secondary motions have remarkable influences over the distribution of momentum and turbulence, indicating that wind-wavy boundary conditions resulting from a balance between diffusion and dissipation of TKE is capable of reproducing the realistic scales of phenomena. |
Databáze: | OpenAIRE |
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