| Thesis Details |
 Title | A Saturation-Dependent Dissipation Source Function
for Wind-Wave Modelling Applications |
|
Author | Alves, Jose Henrique Gomes de Mattos |
|
Institution | University of New South Wales |
|
Date | 2000 |
|
Abstract | This study reports on a new formulation of the
spectral dissipation source term Sds for wind-wave
modelling applications. This new form of Sds
features a nonlinear dependence on the local wave
spectrum, expressed in terms of the azimuthally
integrated saturation parameter B(k)=k^4 F(k).
The basic form of this saturation-dependent Sds is
based on a new framework for the onset of
deep-water wave breaking due to the nonlinear
modulation of wave groups. The new form of Sds is
succesfully validated through numerical
experiments that include exact nonlinear
computations of fetch-limited wind-wave evolution
and hindcasts of two-dimensional wave fields made
with an operational wind-wave model.
The newly-proposed form of Sds generates integral
spectral parameters that agree more closely with
observations when compared to other dissipation
source terms used in state-of-the-art wind-wave
models. It also provides more flexibility in
controlling properties of the wave spectrum within
the high wavenumber range. Tests using a variety
of wind speeds, three commonly-used wind input
source functions and two alternative
full-development evolution limits further
demonstrate the robustness and flexibility of the
new saturation-dependent dissipation source term.
Finally, improved wave hindcasts obtained with an
implementation of the new form of Sds in a version
of the WAM model demonstrate its potential
usefulness in operational wind-wave forecasting
applications. |
| Thesis
|
01front.pdf 70.8 Kb
02whole.pdf 3224.4 Kb
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