10. Numerical Modelling
321
State is described as the sunimation of infinité number of liuear monochromatic waves represented by a unique wave height as a fonction of wave
frequency and the propagation direction. For an individuel wave train, the
rate of change of wave energy (or action) flux is balanced by the wave
energy transfer among different wave components in different directions
(i.e.. wave réfraction and different frequencies fi.e., nonlinear wave Intel
action) as well as energy input and dissipation. This wave eneig\ *pn liai
model. when linked to an atmospheric model. may be adoptai to foie
cast global océan wave climate. One of the earlier attempts on wave «per
tral model is WAAI WAve prédiction Model) (Uasselmann rf o. . I9SN1
This model balances the évolution of the wave speetvum with the hiiiii
of the local wind input. wave dissipation and nonlinear \\a\e wave Intel
action with the considération of incoming swell that are from non le. al
sources. The source ternis describing the wind input. nonlineni Iraimlei ol
energy, dissipation due to wave breaking. bottom dissipation, and reliai
tion for finite-depth water are prescribed explicitly. The model Is lin mu
lated in spherical longitudinal and latitude coordinates l'or an iirhlliniv
région.
The non-inclusion of the diffraction and application of linenr wnvo I h....y
for describing the wave characteristics are the limit ai ions iu I lie iippllcnl ion
of this approach in the nearshore. This warrants the domain ol inlerml
be a few wave lengths away from the barrier and (liai the correct ions lin
the non-linearities be accounted for. With the above staled biiekgromid,
SWAN — has been developed [Booij et al., 1999; Ris et al., 1999]. SWAN
Simulating Waves Nearshore (Ris et al., 1999) is a wave spectral model
which incorporâtes the effect of currents into the existing wave model to
simulate the wave-current interaction. Since the wave phase data is omit i <•< I
in these types of formulations, they are enabled to generatc meshen nindi
larger than a wavelength, thus made suitable for modelling large domains,
especially deep océans. SWAN can be readily nested in WAM. Sin<< ilm
wave phase information is left out of this model, the wave action pePim m
to wave diffraction cannot be formulated and thus is left to th< s<;op< o!
other models.
10.5.2
Test case: Wave propagation over- wnuta-at deptti
bathymetry
The wave génération wer & restoàted
s
v
v. v»
a région. The grid résolution was fcced aa 1
z 1 £2* T ie urza;
321
State is described as the sunimation of infinité number of liuear monochromatic waves represented by a unique wave height as a fonction of wave
frequency and the propagation direction. For an individuel wave train, the
rate of change of wave energy (or action) flux is balanced by the wave
energy transfer among different wave components in different directions
(i.e.. wave réfraction and different frequencies fi.e., nonlinear wave Intel
action) as well as energy input and dissipation. This wave eneig\ *pn liai
model. when linked to an atmospheric model. may be adoptai to foie
cast global océan wave climate. One of the earlier attempts on wave «per
tral model is WAAI WAve prédiction Model) (Uasselmann rf o. . I9SN1
This model balances the évolution of the wave speetvum with the hiiiii
of the local wind input. wave dissipation and nonlinear \\a\e wave Intel
action with the considération of incoming swell that are from non le. al
sources. The source ternis describing the wind input. nonlineni Iraimlei ol
energy, dissipation due to wave breaking. bottom dissipation, and reliai
tion for finite-depth water are prescribed explicitly. The model Is lin mu
lated in spherical longitudinal and latitude coordinates l'or an iirhlliniv
région.
The non-inclusion of the diffraction and application of linenr wnvo I h....y
for describing the wave characteristics are the limit ai ions iu I lie iippllcnl ion
of this approach in the nearshore. This warrants the domain ol inlerml
be a few wave lengths away from the barrier and (liai the correct ions lin
the non-linearities be accounted for. With the above staled biiekgromid,
SWAN — has been developed [Booij et al., 1999; Ris et al., 1999]. SWAN
Simulating Waves Nearshore (Ris et al., 1999) is a wave spectral model
which incorporâtes the effect of currents into the existing wave model to
simulate the wave-current interaction. Since the wave phase data is omit i <•< I
in these types of formulations, they are enabled to generatc meshen nindi
larger than a wavelength, thus made suitable for modelling large domains,
especially deep océans. SWAN can be readily nested in WAM. Sin<< ilm
wave phase information is left out of this model, the wave action pePim m
to wave diffraction cannot be formulated and thus is left to th< s<;op< o!
other models.
10.5.2
Test case: Wave propagation over- wnuta-at deptti
bathymetry
The wave génération wer & restoàted
s
v
v. v»
a région. The grid résolution was fcced aa 1
z 1 £2* T ie urza;