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

Bad wave propagation with roller model

Germán Aragón, modified 1 Year ago.

Bad wave propagation with roller model

Youngling Posts: 10 Join Date: 6/18/13 Recent Posts
Hello everybody,

I'm working in a laboratory-scale model using delft3d 2DH flow-wave configuration in order to validate morphodinamics in a beach. My model configuration consist in a water level boundary and a several discharge nodes as open boundaries in the flow module and 3 stationary offshore boundaries with a parametric Jonswap spectrum in the wave module. I'm running the model in parallel version (8 cores) and without the roller model i'm be able to obtain stable simulations.

My problem is when roller model is enable. If I plot the wave propagation from the wavm file, i obtein a coherent Hs distribution but when i plot the Hs from the trim file i obtain a bad Hs distribution afected by the parallel-subdomains boundaries. I'm sure I missing something related to the roller model configuration.

I've attached the Hs maps. Thank you in advance!
Germán Aragón, modified 1 Year ago.

RE: Bad wave propagation with roller model

Youngling Posts: 10 Join Date: 6/18/13 Recent Posts
Well, the problem is that roller model is not able to run in parallel. Through activation of the roller model the propagation of Hs is quite different over the domain, especially with high bottom slope changes where the application of these bore formulations is quite unrealistic. I set up another model with Domain Decomposition in order to activate roller model only in the surf zone (detail domain), but I only achieved to run the model if the process is enable or disable in both domains simultaneously, otherwise the model crash with no error message (d_hydro crash in windows!)

Any suggestion? Has someone achived that?

In addition, I found very interesting that only using roller model I'm able to obtain a longshore currents and that change all the sedimentary patterns and also the reasonable coefficients of Wbed and Wsus to not obtain huge un-realistic transports.