A03. Waves propagating towards a beach

The bathymetry in this set of tests is identical to the previous one (A02); this time SETUP is activated. The purpose of this test is to verify the correct implementation of the complete model for various grids (1-d, regular, curvilinear, repeated). Plot output includes force and setup.
There is no case with repeated grid, because setup does not work properly in combination with a repeated grid.

A domain with flat inclined bottom is considered. The depth decreases from 10 m at y=0 to depth -1 m at y=4000 m.
At the Southern boundary an incident wave field is assumed which propagates in a direction 30° from S. The peak period is 10 s.

In this series of tests there are no analytical tests to compare with, so the 1-d results are used as a basis for comparison in the graphs.

7 cases are considered:

1d computation
regular 2d grid in standard orientation
regular grid rotated over 10 degr.
curvilinear 'wavy' grid, the grid can be seen in plot A03d.plt
curvilinear 'jagged' grid, the grid can be seen in plot A03e.plt
curvilinear 'jagged' grid, the grid can be seen in plot A03f.plt
spherical coordinates
It is seen that the curvilinear grids do not resolve the wave field well near the beach. These grids are not well adapted to the shoreline. They would probably perform better if they would be better adapted.

2 additional cases show the influence of the directional spreading on the wave set-up:

1d computation with normal incidence and a large directional spreading
1d computation with normal incidence and a narrow spectrum
It appears that with the narrow spectrum the set-up is a little more than 10% of the incoming significant wave height; with a wide spectrum the set-up is somewhat lower (the difference is roughly 20%)

© 2012: Nico Booij