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Dear friends
I have been simulating velocity and water depth of a meandering river with telemac2d these days.A difficulty in attachments always troubled me.I have tried many times with the same stetting except the caculatation mesh(but with the same Edge growth ratio 1.2 and Default edge length 2).However,sometimes I can get success, sometimes I get failed as attachments.Could you tell me what mistake I have make and what should I do.

Hello,

if you have a hunch that the issue is related to your mesh you could use the "CHECKING THE MESH = true" option in your case file and see if there is a neighbouring problem.

Another option is to use other meshing tools (there are plenty out there) to creare a new mesh from scratch or simpply to check and identify thin triangles in your mesh or local connectivity issues within your elements that are somewhat difficult to catch in Bluekenue.

This could also be related to your boundary nodes getting "dry" in specific scenarios (which leads to instabilities around) because you are not imposing the proper conditions there. Try to always check that your boundary have wnough water level even if that implies extra calculation for an artificial warming period.


If you are using a parallel setup, varying the number of parallel processors in your case file could also be profitable, there are some rare cases where eg. 12 parallel processors are a pain to mantain stable but 11 or 10 are flawless. Also, try not to split your domain too much to avoid over-communication between cores/nodes.

This is my go-to , initial sanity check in every single model,


Hope it helps.

José Díaz.

Hello José Díaz
Thank you very much.I have checked my mesh using the first method you advised, and it worked.Could you tell me some other meshing tools you mentioned which can support Pre-Fudda. Besides Bluekenue,I can only use ICEM to build mesh.
Thank you again. Reply will be appreciated very much.
Best regards,
Fakai Lei

Fakai Lei,

You could use Aquaveo SMS meshing module (which supports native 2DM), ChESHER which is a opensource/github project led by member of the forum (Reinhard Fleissner
), meshers based on gmsh, Triangle library (and its variants), MIKE meshes or AdCIRC meshes imported to bluekenue, there is also a somewhat semi-public tool in the SALOME plattform; for GIS pre processing/post processing: Artelia's PostTELEMAC plugin for QGis, Lutra consulting's Crayfish plugin, BASEmesh plugin for QGIS

And there is always the reliable Do-it-yourself way and code/adapt new meshing tools using something like e.g. Python or Matlab.

regards,

José Díaz.