Estuarine Flooding and Dewatering Simulation |
| YR5-mesh.gif (8.1kb) | Finite element grid (1409 nodes and 2415 elements) |
| YR5-bat2d.gif (17.4kb) | Color map of bathymetric depth |
Comments:
The computational grid, named
YR5 for the
Oyster River is created using linear equilateral triangles
fitted to the shoreline boundary. There are 1409 nodes and 2415 elements.
The bathymetric depth contour
reveals a center channel running north to
south.
M2 tidal forcing is specified as a Dirichlet elevation boundary condition
across the southern inlet boundary at the bottom. The
amplitude is 0.83m. The
simulation was started with fluid at rest and was terminated after
six M2 tidal period (74.52hrs). The simulation setup is
given below. All the simulation parameters are summarized in Table below.
| Description | Parameters |
| Bathymetry range | 0 - 8.79m |
| Porous layer thickness | 0.25m |
| Hydraulic conductivity | 0.0003162 |
| Drag coefficient | 0.0025 |
| Time increment | 111.78sec |
| Time steps per tidal period | 400 |
| Tidal periodicity | 12.42hrs |
| Duration of simulation | 74.52hrs (6 cycles) |
| Numerical implicity | 1 (fully implicit) |
| Number of nonlinear iterations | 10 |
| yr5-mb2.gif (12.2kb) | Time series of the total fluid volume and the cumulative transport across the five transects |
| yr5-ts4.gif (13.7kb) | Time series of normal velocity, normal transport, normal bottom stress, and normal sediment transport across five transects |
Comments:
Time history of the total fluid volume and the cumulative transport across
five selected transects as shown in
YR5
show the system establishes a dynamic equilibrium rapidly, and mass
conservation is thereafter maintained throughout the simulation after
the initial tidal period. The maximum normal velocity across the transects
increases then decreases as one moves westward while the normal transport across the same transects
decreases to maintain mass conservation. It is noticed that asymmetry exists
between flood and ebb.
Residual transport:
| yr5-resq.gif (12.4kb) | Oyster River |
| yr5-resv.gif (13.1kb) | Oyster River |
| yr5-ress.gif (11.3kb) | Oyster River |
| yr5-rest.gif (10.9kb) | Oyster River |
Comments:
| yr5-ebb.gif (17.9kb) | Maximum ebb at dynamic equilibrium. |
| yr5-fld.gif (19.4kb) | Maximum flood at dynamic equilibrium. |
| yr5-hv.fli (0.61Mb) | FLC animation of tidal time transport (H*v) |
| yr5-v.fli (0.44Mb) | FLC animation of tidal time velocity (v) |
Comments:
The above transient solutions are numerically well-behaved and appear to
describe the realistic dynamics of the tidal flooding and dewatering process
in this complex domain.


Last modified: September 21, 1998 (Safak Nur ERTURK)