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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

MPI - Running parallel on windows

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Li Haijun, modified 6 Years ago.

MPI - Running parallel on windows

Dear all,
Has anyone tried running the delft flow executable in parallel using MPI mpich2 on windows?
I have run the example provided on a computer server with 12 CPUs and 24 cores and it worked well. But when I run my own flow(3d) model, it does not speed-up so much.
Does anybody know why?How many CPUs and cores should I use in order to achieve the optimal computation?Should I rebuild and recompile the open source to get the MPI running version of Delft3D?

Thanks in advance
Li Haijun
AM
Arjen Markus, modified 6 Years ago.

RE: MPI - Running parallel on windows

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts
Li Haijun, you sent this to the part of the forum that is devoted to water quality modelling. I think you meant to send it to the FLOW part instead.

Delft3D-WAQ does have some multiprocessing features, but they are most useful in the context of evaluating the processes in parallel and for that we do not use MPI but OpenMP.
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Li Haijun, modified 6 Years ago.

RE: MPI - Running parallel on windows

Hi Arjen,

Thank you for your reply.

I may send a new post to the FLOW part. Exactly I run a FLOW model instead of WAQ.

Regards,

Li Haijun
Adri Mourits, modified 6 Years ago.

RE: MPI - Running parallel on windows (Answer)

Yoda Posts: 1212 Join Date: 1/3/11 Recent Posts
Hi Li Haijun,

Please have a look at the FAQ.

Regards,

Adri
U
Li Haijun, modified 6 Years ago.

RE: MPI - Running parallel on windows

Hi Adri,

My model has a mmax of 186 and a nmax of 482. Does it mean that the number of partitions(ONP) should be lower?
I run the model in MPI parallel using 2 CPUs and 2 cores for fastest computation. However, the time it costs nearly the same as computation without MPI. Sometimes it even slower. Maybe it's better to just run it without MPI parallel.

By the way, should I compile the source again with MPI environment in the Visual Studio 2010 to run a right MPI parallel computation of FLOW?

Thank you,

Li Haijun