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Kristian Ravnkilde
May 7, 2014, 07:07 AM
As models are getting bigger, meshing is becoming a major time waster. It would be good to have mesher re-coded to use multiple cores, and more effectively - at the moment it chugs along using one only, and that only for a fraction of the time and for several hours on some models, longer than running a one day simulation. And when you may have to re-mesh several times as you try to make that stupid river reach* behave itself properly, that can lose you a lot of time, to say nothing of losing track of what you were doing. Plenty of RAM there for it, although our network could be quicker ..........

* There's always one :mad:

Duncan Kitts
May 13, 2014, 08:36 AM
Hi Kristian,

Nice idea but unfortunately the parallelisation of unstructured meshing is still very much in it's research infancy. I suspect it'll be some time before the meshing algorithm that Infoworks 2D uses (Shewchuk) is parallelised and then even longer before this is added to the software. The most time-consuming aspect of meshing is where there are small triangles and elements. Reducing the number of these and being proactive with this is the best way to go. Making sure your data is clean is key. The following blog should help:-

http://blog.innovyze.com/2014/01/13/tips-for-a-good-meshing-experience-2/

Also, when I create a 2D mesh, I build in the detail bit by bit. You can troubleshoot river reach connections and additional mesh detail (mesh zones etc...) using a coarser mesh and then add the detailed finer mesh once these issues have been overcome and you are ready to undertake the final simulations. This should speed up the process.