Numerical modeling of waves for a tsunami early warning system

Numerical modeling of waves for a tsunami early warning system
experimental results are cut at that frequency in order to compare the same
range of frequency. Now similar considerations can be made, when a near
ηS15(m)
ηS24(m)
ηS16(m)
0.02
0.01
0
−0.01
−0.02
0.02
0.01
0
−0.01
−0.02
0.02
0.01
0
−0.01
−0.02
15 20 25 30
15 20 25 30
15 20 25 30
t(s)
ηS22(m)
ηS19(m)
0.02
0.01
0
−0.01
−0.02
0.02
0.01
0
−0.01
−0.02
15 20 25 30
15 20 25 30
t(s)
Figure 4.32: 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 12S to estimate the wave source
term.
field sea level gauge is used to determine the source term and the wave field
is calculated at all the other gauges by means of the inversion technique. The
laboratory registration of the free water surface elevation at the gauge 12S
is taken as the available measurement to correct the pre-calculated unitary
simulations. In the following figures, as for the previous one, the red dashed
lines refer to the physical model results and the solid black lines to those of
the numerical model. In figure 4.31 the comparison of the free water surface
elevation is shown at the near shore gauges. The comparison at the gauge
12S is perfect because mathematically imposed; at the gauges 7S and 10S
the numerical model reproduces a high frequency wave packet which does not
compare in the physical model. Looking at the figure 4.32 this discrepancy
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