An example of the iterative behaviour of Swan

The area considered in this example is the Friese Zeegat, a tidal entrance between two islands in the North of the Netherlands. The bathymetry is shown below:

The number of iteration was fixed to 30 by means of the command
num accur npnts=101. stat 30
The default stopping criterion was reached after 11 iterations. It is seen in the graphs below that after 30 iterations there still was slow change in the value of Hs and larger change in the average period.
The graphs to the right show Hs (upper panel) and Tm (lower panel) as function of iteration.
The graphs were obtained by means of the post-processing software OPGraph; click to see the control file.

The difference in Hs (known as DHS in the user manual) and Tm (DRTM01) is indication where the largest variation is taking place.
The graph shows dHs (in m) after 30 iterations.
It is reassuring that the largest values of dHs occur outside the region of interest, which is the tidal entrance between the two islands.
The pattern can change appreciably during the computation.
The figure shows the values of dHs after 10 iterations. At first sight it appears that the area where changes take place is larger after 30 iterations; however, the values are much smaller after 30 iterations.
This figure shows the values of dTm (in s) after 10 iterations.

go to top

© 2012: Nico Booij