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. 




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



Message Boards

Background horizontal eddy viscosity reset for (m,n)

Rafael Casares, modified 8 Years ago.

Background horizontal eddy viscosity reset for (m,n)

Youngling Posts: 17 Join Date: 12/9/11 Recent Posts
Hi, everybody.

I've got the following warning messages after running the flow module:

WARNING Background horizontal eddy viscosity reset for (m,n)
WARNING Background horizontal eddy diffusivity reset for (m,n)

Does this mean that the viscosity and diffusivity values assigned to the model are wrong?

I am using the default values of 1 m2/s for horizontal eddy viscosity and 10 m2/s for diffusivity, just to try.

What does "reset" mean for the model?

Any suggestion? Thanks in advance.

Adri Mourits, modified 8 Years ago.

RE: Background horizontal eddy viscosity reset for (m,n)

Yoda Posts: 1221 Join Date: 1/3/11 Recent Posts
Hi Rafael,

They are dependent on the grid size. See the manual, section "4.5.3 Timeframe" and "9.5 Turbulence".