"Assign BC...". In the "RMA2 Assign Boundary Condition" window, pick the ` ead BC"
H
option. Set the elevation (lower part of the window) to 5.0. This value is used to tell
CGWAVE that this nodestring is an open boundary. Click "OK". Repeat this procedure
for all other boundaries. For all boundaries other than the open boundary, the elevation
value represents the reflection coefficient and should be between 0.0 and 1.0,
corresponding to the reflection coefficient of that portion of coastal boundary (including
islands). The value of 1.0 for reflection coefficient should be used for a fully reflecting
boundary and 0.0 used for fully absorbing boundary.
Save the boundary condition
information by selecting "Save BC..." from the "RMA2" menu. For the example case,
name the file "swanst.bc".
Floating Structures. Floating structures are discussed in detail in section 4.5.
When a floating structure is included inside the domain, the elements containing the
floating structure must be both marked and adjusted to signify and account for the
presence of the structure. The elements contained by the area of the floating structure are
assigned a "Material Type ID" of "3" as follows. First, select all the elements within an
area bounded by the perimeter of the floating structure. Then select "Assign Material
Type" from the "Elements" menu. Click on the "New" button in the "Materials Editor"
until the "ID:" changes to "3". Click "Select". Next, modify the depth of the nodes in this
area as described in section 4.5. The new depths are shown in Figure 6 as d . This can be
done using the "Transform Mesh" option found in the "Nodes" menu. CGWAVE will
now recognize this area as a floating structure and treat it accordingly.
definition, the grid must be renumbered. Using the "Select nodestring" tool, select any of
the nodestrings. From the "Elements" menu choose "Renumber". In the "Renumbering
Opts" window, select "Band Width" and then "OK".
After renumbering, the grid
generation process is complete. Re-save the geometry and boundary condition files using
the same names given before (swanst.geo and swanst.bc). Some basic information about
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