Wind-wave generation by energy and momentum flux to the forced components of a wave field
- 12 April 1978
- journal article
- Published by Cambridge University Press (CUP) in Journal of Fluid Mechanics
- Vol. 85 (3) , 543-572
- https://doi.org/10.1017/s0022112078000786
Abstract
The response of surface gravity waves with profile ζ to forcing by the atmospheric pressure p(a) is studied. It is shown that not only the usually considered cross-spectrum 〈p(a)ζ〉 is responsible for wave growth. All higher-order spectra 〈p(a)ζ1,…,ζn〉 also lead to wave growth linear in ε = ρ(a)/ρ,ρ(a) and ρ being the density of air and water respectively. The bispectral contribution is investigated in detail and is calculated for three models of the bispectrum. The results indicate that bispectral contributions are not negligible and may account for typically 30-50%, and possibly more, of the usually considered cross-spectral contribution. The bispectral growth mechanism contains the fluctuating-stress mechanism discussed by Longuet-Higgins (1969) as a special case. As a byproduct new information on the symmetry properties of the hydrodynamic coupling off the dispersion shell is obtained.Keywords
This publication has 7 references indexed in Scilit:
- The growth of waves by modulated wind stressJournal of Geophysical Research, 1976
- On the Interaction Between Long and Short Surface WavesJournal of Physical Oceanography, 1976
- Action of a Variable Stress at the Surface of Water WavesPhysics of Fluids, 1969
- WEAK-INTERACTION THEORY OF OCEAN WAVESPublished by Elsevier ,1968
- Variational methods and applications to water wavesProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1967
- Nonlinear interactions treated by the methods of theoretical physics (with application to the generation of waves by wind)Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1967
- On the generation of surface waves by shear flowsJournal of Fluid Mechanics, 1957