Open AccessEstimation of Kinetic Energy Dissipation from Breaking Waves in the Wave Crest Region
Author(s) -
J. H. Lee,
Jason Monty,
John Elsnab,
Alessandro Toffoli,
Alexander V. Babanin,
Alberto Alberello
Publication year - 2017
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/jpo-d-16-0273.1
Subject(s) - breaking wave , dissipation , turbulence kinetic energy , turbulence , physics , particle image velocimetry , wavenumber , wave turbulence , kinetic energy , mechanics , wind wave , phase velocity , wave propagation , isotropy , crest , computational physics , optics , classical mechanics , thermodynamics
Wave-induced turbulence due to breaking in the absence of surface shear stresses is investigated experimentally. A high-fidelity particle image velocimetry (PIV) technique is used to measure the turbulence near the water surface, inside the wave crests. The spatial velocity vector fields of the breaking waves acquired from PIV provide accurate vertical velocity profiles near the air–water interface, as well as wavenumber velocity spectra beneath the breaking waves at different depths. These velocity spectra exhibit a Kolmogorov interval at high wavenumbers, indicating the presence of isotropic turbulence and permitting an estimation of energy dissipation rates. The depth dependence of dissipation rates of the breaking waves generated in the laboratory shows a scaling similar to that found in wind-forced breaking waves in the field. A phase dependence in the dissipation rates of turbulence kinetic energy is also observed, which should be considered to improve the accuracy of the estimated and modeled wave energy dissipation.