The Response of Wind Ripples to Long Surface Waves.
Abstract
Further refinement of the rate of wave amplification by wind has resulted from laboratory measurements and numerical calculations. Calculations of the nonlinear interactions in the capillary-gravity range have been extended. We developed a new comfortable method for description of the nonlinear gravity waves interactions on deep water. A Boltzmann's collision term in the Hasselmann's equation was replaced by a nonlinear diffusive operator. The model equation has the same constants of motion as the exact equation and gives correct expressions for weak turbulent Kolmogorov spectra. A numerical simulation of the new model demostrates a pretty good coincidence with the results of solution of the Hasselmann equation. The new model can be efficiently used in the study of physical mechanisms of air-sea interaction. We studied numerically the weak turbulence of capillary waves on deep water. By a direct solution of the Euler equation in approximation of small angles we found that stationary spectra of capillary waves obey the Kolmogorov law KA(.19/4) which is exact solution of kinetic equation for waves. In situation when the turbulence is realized in finite-size tank there is completely new effect of "frozen" turbulence which could be realized at very low levels of the excitations of capillary waves. At "frozen" turbulence regime there is no energy flux from low wavenumbers of pumping toward high wavenumbers of damping.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 18, 1998
- Accession Number
- ADA356642
Entities
People
- Mark A. Donelan
- Vladimir E. Zakharov
- Vladimir K. Makin
- Vladimir N. Kudryavtsev
Organizations
- University of Arizona