What mesh generation software do you use?

Mesh generators, CAD programs, and other tools

What mesh generation software do you use with Elmer?

ElmerGUI (netgen or tetgen plugins)
12
9%
Gmsh
61
44%
Netgen
13
9%
ElmerGrid (native .grd format)
11
8%
GiD
1
1%
Ansys
3
2%
Gambit
0
No votes
Comsol Multiphysics
2
1%
Salome
29
21%
Something else (please specify)
7
5%
 
Total votes: 139

raback
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Re: What mesh generation software do you use?

Post by raback »

Hi Mark

If there is no existing import format it may just be a few hours of work to add one. Usually this goes in the following steps

1) Explore the output formats of the mesh generator and see what could be useful starting point. Often there is no documentation but of course better if there is.
2) Make several minimal examples featuring different elementtypes
3) Write a parser such that it can deal with the small examples.
4) Test it with real examples

Of these 1), 2) and 4) can be done by an interested user. Time permitting doing 3) should not be too much for the development team. However, it is essential that there is a good format to work on. For Femap this is probably the case as it is intended to be a general purpose mesh generator.

-Peter
gforti
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Re: What mesh generation software do you use?

Post by gforti »

Hello all,

Can I use the output files from Triangle (https://www.cs.cmu.edu/~quake/triangle.html) witth Elmer?
Rich_B
Posts: 421
Joined: 24 Aug 2009, 20:18

Re: What mesh generation software do you use?

Post by Rich_B »

Hello,

If you open a command window and enter 'elmergrid', it will output help text. Look for input formats, and you will find format 11 is for Triangle.

run elmergrid like this:
elmergrid 11 2 filename -autoclean
and it should generate the Elmer mesh files.

Rich.
gforti
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Re: What mesh generation software do you use?

Post by gforti »

Hello,

Thanks. Code is running but files are not being created.

it finishes like this:
LoadTriangleInput: elem i=21131 j=21130
LoadTriangleInput: elem i=21132 j=21131
Loading nodes from file trafo_aniso_lin.poly
Creating an inverse topology of the finite element mesh
Attachments
mesh.zip
(478.49 KiB) Downloaded 51 times
Rich_B
Posts: 421
Joined: 24 Aug 2009, 20:18

Re: What mesh generation software do you use?

Post by Rich_B »

Hello,

I get the same result. Do you have another way to check that the input files are valid?

Attached are two examples of Triangle format that Elmergrid can convert properly.

Rich.
Attachments
box.zip
(832 Bytes) Downloaded 50 times
Apoly.zip
(1.99 KiB) Downloaded 47 times
kevinarden
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Re: What mesh generation software do you use?

Post by kevinarden »

It is probably version issues. Both codes are old. Triangle seems to have been abandoned the latest version 1.6 was 2005. ElmerGrid started 1995. It is not likely that ElmerGrid kept up with Triangle versions since they quite in 2005. I think it is probably a mismatch in format due to version releases.
gforti
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Re: What mesh generation software do you use?

Post by gforti »

I think the code for *.poly generation file is broken.
raback
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Re: What mesh generation software do you use?

Post by raback »

Hi,

Is there some flag to force indexing to start from 1. The sample seems to have C-style indexing. It is not hard to code but if it is a flag in Triangle maybe not worth the effort.

The fresh "devel" has some improved diagnostics.

-Peter
raback
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Re: What mesh generation software do you use?

Post by raback »

Hi,

Just added the offset but it seems that the .poly file is indeed broken. The old logic does not make sense in interpreting this one. I can change the code, but what is the logic that covers both of the cases?

-Peter
gforti
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Re: What mesh generation software do you use?

Post by gforti »

Is there a way to do the conversion without the poly file?
Regarding my broken poly file, best is for me to try fixing it.
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