Google+
Facebook
LinkedIn
Twitter
Digg
StumbleUpon
Home
Download PDF
Order CD-ROM
Order in Print
Home
>
Coastal and Hydraulics Laboratory Fact Sheets
>
> Circular Island
Figure 21. Harbor response curves for various values of the friction factor
Figure 22. Cross section of island and shoal bathymetry
cgwave_man3
Page Navigation
93
94
95
96
97
98
99
100
101
102
103
8.4
Circular
Island
In
this
example
problem,
we consider
the
propagation
of
long
waves
around
a
circular
island is
simulated.
Homma
(1950)
and
Jonsson,
et
al.
(1976)
showed
that
extensive
scattering
occurs
for
long
waves.
This
case
tests
and
demonstrates
the
ability
of
CGWAVE
to handle
strong
scattering
effects
with
a
relaxed
(Xu
et
al.
1996)
boundary
condition.
This
boundary
condition
allows
the
model
to be applied to a greater
range
of
modeling
problems,
as it
does
not
require
full
reflection
of
the
coastline
outside
the
model
domain.
The
modeled
domain
(Figure
22)
consists
of a
circular
island on a shoal
with
a
parabolic
variation
in
depth.
The
island
has
a radius of 10
km.
The
open
boundary
is
placed
at a radius of 35 km
from
the
center
of
the
island.
The
minimum
water
depth
is
444 m at
the
edge
of
the
island
and
increases
to 4000 m at
the
outer
edge
of
the
shoal.
The
domain
has
constant
depth
beyond
the
shoal.
Incident
wave
periods of
240,
410
and
480
seconds
are
considered.
Figure
23
shows
the
results
for
the
240
second
incident
wave
condition.
This
figure
has
been
divided
in
half
due to
symmetry
of
the
solution.
Waves
are
incident
from
the
left.
The
upper
portion
is
the
analytical
solution,
the
lower
portion
is
the
CGWAVE
result.
The
CGWAVE
results
match
the
analytical
solution.
Notably
absent
are
signs
of
artificial
boundary
effects
near
the
open
boundary.
Similar
results
were
obtained
for
the
longer
wave
periods,
with
results
matching
the
analytical
data.
97
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
Previous Page
