Numerical modeling of waves for a tsunami early warning system

ηS15(m)
ηS24(m)
ηS16(m)
Numerical modeling of waves for a tsunami early warning system
0.02
0.01
0
−0.01
−0.02
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0
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15 20 25 30
15 20 25 30
15 20 25 30
t(s)
ηS22(m)
ηS19(m)
0.02
0.01
0
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15 20 25 30
15 20 25 30
t(s)
Figure 4.28: Comparison of the free surface elevations at the far field gauges
position, measured (red dashed line) and obtained from the numerical model
(black solid line). The numerical results are achieved by using the registration
of the free surface elevation at the gauge 15S to estimate the wave source
term.
measurements, while the black solid lines the numerical model solutions. In
figure 4.27 it can be noted an overall good agreement in the comparison,
but, specially for the comparison at the gauges 12S, 20S and 11S, the
numerical model seems not able to reproduce exactly the experiments. This
can be explained by the fact that those gauges are the ones located closer to
the landslide impact and in shallower waters where the waves are generally
complex and nonlinear. At these gauges it appears a wave pattern at high
frequency component which are not modelled numerically (see after figure
4.30 of wave energy spectra).
Looking at the figures 4.28 and 4.29, an overall good agreement is
achieved, specially in the comparisons at the gauges located in the far field
(figure 4.28). About these first simulations it can be said that, when using
a far field registration in order to estimate the waves source term, the wave
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