open TELEMAC-MASCARET The mathematically superior suite of solvers

Gmsh is a powerful program to generate unstructured grids in a rather flexible way. As an example, I enclosed a picture of a mesh of the Belgian coast and the mouth of the Scheldt estuary, with mesh size depending on the distance to the coastline and the bathymetry.

Its main drawback for TELEMAC users is that it cannot export grids into SLF mesh files or generate CLI boundary condition files.

That is why we implemented a Matlab package at Flanders Hydraulics Research (Antwerp, Belgium) whose main purpose is to load information from Gmsh grid and save it into SLF and CLI files. It can also been used to generate the domain contours from different types of database, to interpolate bathymetry information on the grid and save it in the SLF file, to display the grid on Google Earth, ...

A first version of the package may be downloaded on my personal website www.oliviergourgue.net/download

We hope it can be useful for others and we are very interested in any feedback or suggestion from you for future developments.

Hello,

Congratulations and many thanks, we'll surely advertise your Matlab package. Is Gmsh a free mesh generator or is it commercial ?

With best regards,

Jean-Michel Hervouet

Thank you for your answer. Yes, I should have mentioned that Gmsh is open source and can be downloaded at www.geuz.org/gmsh

Thank you so much for your contribution. It would be great if you can tell more about how to use this tool.

Best Regards

Huy

Thank you Huy for your post.

You can find the last version of the toolbox on my webpage www.oliviergourgue.net/pug/ or clone the github repository github.com/ogourgue/PUG .

There are some example scripts in the example folder. But I agree, it lacks a small tutorial to explain how to use it step by step. I keep that in mind and will do as soon as I have the time.

In the meantime, do not hesitate to try it (several ones already did it) and ask me specific questions if needed.

Olivier.

Thank you so much Olivier for your quick reply. Hopefully, we can see a step-by-step tutorial soon as it is very useful for MATLAB & TELEMAC beginners to embrace fully the power of your tool. Otherwise, I will try it first.

Best Regards

Huy

Unfortunately, it won't be for the coming weeks :-s

Hello,

I have also produced a python tool to generate a selafin geometry file from gmsh. It isnt really something that I would be proud of distributing as it is an option in a program that was originally used to create the grid files for FVCOM. So the code is pretty much spaghetti like in its structure.

I also have python code that generates attractors for gmsh (allows grid refinement along boundaries or arbitrary locations within the grid, and assembles the boundary line strings required, with user defined spacings. Also allows specification of boundary interfaces along the edge lines. Most of it is driven by GIS files or databases feeding into python code. My method is to create the driving files for gmsh, then open gmsh and run the mesh generation, then use python to read the mesh files to convert to selafin.

I will see if I can get some of this code cleaned up for passing on.

I have been using gmsh for several years now and find it a very useful program. There are Many features that I don not use.

Cheers
John

Hello John,

Maybe we can hel in cleaing up the code. Note the TELEMAC plugin for Q-GIS. Maybe you could integrate similarly to that ?

In any case, don't worry about your code not being cleaned etc. We would be happy to have a look.

Sébastien.

For now it will have to wait as I am of on 4 weeks leave to ski Japan.

Will continue this discussion after that ...

Cheers
John