M.Sc Thesis | |

M.Sc Student | Zeisel Amit |
---|---|

Subject | Wind Waves Generation |

Department | Department of Civil and Environmental Engineering |

Supervisors | PROFESSOR EMERITUS Michael Stiassnie |

PROF. Yehuda Agnon | |

Full Thesis text |

This
study deals with the problem of wind waves generation. Scientific interest in
momentum and energy transfer between the ocean and atmosphere and wave
forecasting are examples of directly related research topics of the wind waves
generation problem. The problem deals with the instability of water waves in
the presence of a shear flow. The study contains a full formulation of the
linear stability problem in ** 2D** for the viscous and inviscid
models. The formulation leads to an ODE which controls the problem. The governing
equation for the inviscid model is Rayleigh's equation, whereas the governing
equation for the viscous model is the Orr-Sommerfeld equation. After applying
the boundary conditions the resulting problem is an eigenvalue problem for the
wavenumber or for the wave frequency. These eigenvalue problems were solved
using numerical methods chosen especially for each model. The mean flow of the
air and water plays a main role in the problem because the solution is
sensitive to this choice. We use three versions of the mean flow profile; two
of them are profiles which have been used in previous studies and one of them
is a new profile which we suggest as a more physical profile. The results were
calculated for both models and many different scenarios. In the viscous model,
we expand the range of wavelengths and wind intensities with respect to previous
studies to