MIKE 21 BW, User Manual, Page: 47 / 196

2DH Boussinesq Wave Module - Examples
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Figure 4.22 Generation of internal wave boundary data using the MIKE 21 Toolbox
'Random Wave Generation' tool
The length of the simulation is 30 minutes (corresponding to 18001 time
steps). The computation time depends on the speed of your PC. For a laptop
IBM T40 Pentium M (Centrino, 1.6 GHz and 1GB DDR RAM) the required
system time is approximately 11 hours (the system CPS is approximately
200,000 points/second).
You may reduce the length of the simulation in order to reduce the overall
CPU time.
Model results
Figure 4.23 shows a 2D visualisation of the simulated instantaneous surface
elevation. You can make a similar plot by loading (drag and drop) the PFS-file
MzPlot.Surfaceelevation.plc into the MIKE Zero shell during or after model
execution. From the figure is seen that the intensity of the high-frequency
waves is larger in the shallow water parts (say, depths less than 6 m) than at
the offshore boundary as the quadratic nonlinear energy transfer is larger in
shallow water than in deep water. Some of the generated high-frequency
waves (say, wave periods less than 2-3 s) may not be properly resolved.
However, they will affect the simulated long waves marginally.
Figure 4.24 shows a 3D visualisation of the simulated instantaneous surface
elevation. The surface rollers are shown in white. You can make a similar plot
by opening (by double-clicking) the PFS-file 'Anim Directional Waves with