N
OPEN OCEAN BOUNDARY
Fig. 11: a.) Computational grid for the idealized inlet of test case 3 and b.) details of the grid in the
vicinity of the inlet.
4.3
Test Case3:
Idealized Inlet
In this problem, we apply the model to the case of an idealized inlet as shown in Fig.
11. The domain consists of a 10 km by 20 km sound connected to the open ocean through an
inlet which is 1 km wide and 0.5 km long. The open ocean boundary is 20 km from the entrance
of the inlet and is 50 km wide. The initial bathymetry in the sound and through the inlet is
constant at a depth of 5 m. South of the inlet the bathymetry varies linearly from 5 m at the
entrance to 14 m at the open ocean boundary. The sediment density and median grain size are the
same as those specified in the previous problem. The grid for the problem is also shown in Fig.
11 with the inset showing the details in the vicinity of the inlet. The nodal spacing ranges from
100 m near the inlet to 1 km at the open ocean boundary. The problem is forced with an M2 tide
with a 15 cm amplitude which produces a maximum current of approximately 1 m/s through the
inlet. The time step used for the hydrodynamics is 5 seconds, and the bed is updated every 50
hydrodynamic time steps. A 28 day simulation was run with magnified sediment transport rates
29