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DELWAQ

DELWAQ is the engine of the D-Water Quality and D-Ecology programmes of the Delft3D suite. It is based on a rich library from which relevant substances and processes can be selected to quickly put water and sediment quality models together.

The processes library covers many aspects of water quality and ecology, from basic tracers, dissolved oxygen, nutrients, organic matter, inorganic suspended matter, heavy metals, bacteria and organic micro-pollutants, to complex algae and macrophyte dynamics. High performance solvers enable the simulation of long periods, often required to capture the full cycles of the processes being modelled.

The finite volume approach underlying DELWAQ allows it to be coupled to both the structured grid hydrodynamics of the current Delft3D-FLOW engine and the upcoming D-Flow Flexible Mesh engine (1D-2D-3D) of the Delft3D Flexible Mesh Suite (or even other models such as TELEMAC).

'DELWAQ in open source' is our invitation to all leading experts to collaborate in further development and research in the field of water quality, ecology and morphology using Delft3D. Feel free to post your DELWAQ related questions or comments in this dedicated forum space. If you are new to DELWAQ, the tutorial (in the user manual) is a good place to start. A list of DELWAQ related publications is available here.

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Sub groups
D-Flow Flexible Mesh
DELWAQ

Cohesive sediments & muddy systems

 


Message Boards

run DELWAQ on a cluster?

U
Zhanxian Wang, modified 2 Years ago.

run DELWAQ on a cluster?

Hi, all,

I have a question regarding running DELWAQ on a cluster:

My FLOW model is a 3D z-layer model, and I can run the FLOW model on our cluster on multi-cores using MPI. After switching on "Export WAQ Input" on the FLOW GUI, the FLOW model generates the WAQ related HD files on each sub-domain (e.g. 50 sub-domains if using 50 cores). My question is how can I setup the WAQ model to use these WAQ input files directly and run the WAQ simulation on the cluster?

Thanks,
Jonathan
AM
Arjen Markus, modified 2 Years ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts
The short answer is: you can't. DELWAQ does not support this type of multiprocessing.
The somewhat longer answer is: we are working on the possibility to take advantage of multi-cores in the same way that Delft3D-FLOW/D-FLOW-FM can, but that will take some while yet.

For now the best option is to combine the results from the individual domains using ddcouple/ddcouplefm into a single domain.
U
Zhanxian Wang, modified 2 Years ago.

RE: run DELWAQ on a cluster?

Arjen,

Thanks again for your quick response.

Is ddcouple available for Linux? So far, I have to copy all of the WAQ coupling files from the cluster to a local Windows machine and run ddcouple there to combine the files.

Thanks,
Jonathan
AM
Arjen Markus, modified 2 Years ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts
Hm, that should not be necessary - we use the Linux-version all the time. Let me check this.
MJ
Michelle Jeuken, modified 2 Years ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 154 Join Date: 1/21/13 Recent Posts
Here is a Linux version of ddcouple. This works only for Delft3D 4 structured flow. For Delft3D FM runs you should use ddcouplefm.
U
Zhanxian Wang, modified 2 Years ago.

RE: run DELWAQ on a cluster?

Thanks Michelle!

To be clear, I can still run DELWAQ on a cluster, but not in the MPI mode, right?

Thanks,
Jonathan
MJ
Michelle Jeuken, modified 2 Years ago.

RE: run DELWAQ on a cluster? (Answer)

Jedi Knight Posts: 154 Join Date: 1/21/13 Recent Posts
No, Delwaq can't run in MPI mode, but it can make use of multiple threads on a single node. Add the following line to block 7 of the inp-file:

CONSTANTS nothreads DATA 0.0 ; OMP-parallelism ’on’

Just before #7

Part of the code of Delwaq then makes use of multiple threads when available. Look in the mon-file how many threads were used. The value of 0.0 tries to take as many as available, but you can limit it by giving an specific number.

This will also work on Windows computers
RK
Randall Kiefer, modified 5 Months ago.

RE: run DELWAQ on a cluster?

Youngling Posts: 1 Join Date: 9/29/20 Recent Posts
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