A32. Propagation past a circular obstacle

The purpose of this test is to demonstrate the behaviour of the various stationary numerical schemes for a case where they pass an obstacle. The obstacle is a breakwater which has in plan view the shape of a semicircle (radius 1000m). The situation is sketched in plot A32a.plt.

A domain with deep water is considered. The domain is rectangular; it extends over 2500 m in y-direction and 2500 m in x-direction. The average propagation direction of the waves is -60° (Cartesian convention); the directional distribution is narrow.

At the Northern boundary an incident wave field is assumed. This incident wave field has a BIN spectrum with 5° directional spreading. The wave period is 10 s.

For wave field with 0 directional spread the analytical solution is known. On the Southern boundary it is a step function with the discontinuity on the ray which is tangent to the obstacle.

The graph of Hs on the Southern boundary is shown for: a, the BSBT scheme, b, the SORDUP scheme.

2 cases are considered:

A32a
1st order BSBT scheme
A32b
2nd order upwind scheme

© 2012: Nico Booij