MIKE 21 BW, User Manual, Page: 58 / 196

Examples
58 MIKE 21 BW - © DHI
Also in this example we use ´'Simple upwinding at steep gradients and near
land' for the space discretisation of the convective terms and a time extrapo-
lation factor of slightly less than one (0.8 in this case). Similar settings are
used for the Torsminde Harbour example presented in section 4.2.5.
The time step is set to 0.1 s for the regular wave simulation and 0.05 s for
directional wave simulation. Due to the smaller wave periods (T
min
= 4.5 s)
considered in the directional wave case the time step is reduce accordingly.
Figure 4.33 shows the wave breaking and moving shoreline parameters used
in this application. The roller velocity type is set to 1 as no predominate direc-
tion can be identified for the breaking waves. In the previous example (Tors-
minde Harbour) the type is set to 3 and the predominant wave direction is set
to 270 ºN. The remaining parameters are set as recommended in the User
Guide and Online Help.
Except for the slot depth, which is set to 16 m, default parameters are used
for modelling of the moving shoreline.