MIKE 21 BW, User Manual, Page: 80 / 196

Examples
80 MIKE 21 BW - © DHI
tal section and the shoreline, and an emerged plan beach with a slope of
1:20. A half detached breakwater approximately 266 m long and 35 m wide is
placed parallel to the shoreline along a vertical wall. The onshore side of the
breakwater is located approximately 373 m from the shoreline. An absorbing
beach is placed on the offshore side of the breakwater and along the vertical
wall opposite to the breakwater.
We will consider two different wave situations:

Regular unidirectional waves (PFS file: RegularWaves.bw)
H= 3.2 m, T= 10.7 s and MWD= 270 ºN (normal incidence)

Irregular directional waves (PFS file: DirectionalWaves.bw)
H
m0
= 4.6 m, T
p
= 10.7 s, T
min
= 4 s, MWD= 270 ºN, standard
JONSWAP spectrum, cos2-directional spreading (normal incidence)
The spatial resolution is set to 2 m. As the primary part of the waves is
expected to break where Hmax ~ 0.8
.
h (experience rule for regular waves),
the wave breaking is initiated at 4 m water depth in case of regular waves.
The directional waves will start to break where H
m0
~ 0.5
.
h, i.e. at water depth
9 m. This means the initial breaking waves are resolved by more than 30 grid
points per wave length.