intro story Coast / Estuary

Coast / Estuary

Coastal systems are among the most dynamic physical systems on earth and are subject to a large variety of forces. The morphodynamic changes occurring to coastlines worldwide are of great interest and importance. These changes occur as a result of the erosion of sediments, its subsequent transport as bed load or suspended load, and eventual deposition. 
 
Estuaries are partly enclosed water bodies that have an open connection to the coast. Estuaries generally have one or more branching channels, intertidal mudflats and/or salt marshes. Intertidal areas are of high ecological importance and trap sediments (sands, silts, clays and organic matter).
Within the Delft3D modelling package a large variation of coastal and estuarine physical and chemical processes can be simulated. These include waves, tidal propagation, wind- or wave-induced water level setup, flow induced by salinity or temperature gradients, sand and mud transport, water quality and changing bathymetry (morphology). Delft3D can also be used operationally e.g. storm, surge and algal bloom forecasting. 
 
On this discussion page you can post questions, research discussions or just share your experience about modelling coastal and/or estuarine systems with Delft3D FM. 
 

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Sub groups
D-Flow Flexible Mesh
DELWAQ
Cohesive sediments & muddy systems

 

 

Message Boards

Sand transport problem: Sediment erosion shortage at NM 33460 Fraction?

SZ
Sean Zhang, modified 3 Years ago.

Sand transport problem: Sediment erosion shortage at NM 33460 Fraction?

Youngling Posts: 4 Join Date: 11/17/16 Recent Posts
Dear modelers?

Does anybody know how to deal with sediment erosion shortage error?

I learned it is caused by threshold sediment thickness setting being too small, then erosion happens at one time step in certain grids is more than sediment available, thus lead to negative values like:

Sediment erosion shortage at NM 33460 Fraction: 1 Mass available : -0.2197-318 Mass to be eroded: -0.2197-318
Sediment erosion shortage at NM 33871 Fraction: 1 Mass available : -0.6396-315 Mass to be eroded: -0.6396-315
Sediment erosion shortage at NM 33884 Fraction: 1 Mass available : -0.7035-292 Mass to be eroded: -0.7035-292
....

This can not be solved by setting Threshold sediment thickness smaller, even to zero in my case, as my initial bed sediment thickness is zero and initial suspended sediment concentration is 0.1 kg/m3.

My goal is too check where the suspended sediment goes and deposits at bottom after a period. This problem will not occur for mud, only for sand.



Thanks in advance~

Sean