Automatic interference treatment

[mat]

Hi Louise,

Thank you very much for your help. I followed your instructions and it seems that my RVE is now perfectly periodic!

Best regards,
Mathieu

[louisepb]

Hi Mathieu,

That's great

Let me know if there's anything else you need help with.

Best regards,
Louise

[mat]

Hi Louise,

In order to increase the overall fiber volume content and close the vertical gaps between the yarns, I am performing a compaction simulation of the RVE.
During the simulation, there is some instabilities due to the mesh quality (negative volume in some elements).

Joint to this message are two screenshot of my mesh, one can see that it contains many elements with a poor aspect ratio which later represent a problem for the simulation.
I guess these elements are due to the meshing algorithm implemented in TexGen. Indeed, due to the small gap between the yarns, small strips of elements are created with poor aspect ratios. Do you know if there's a way to improve the mesh quality using TexGen (without reducing drastically the element size) or do you think it would be better to remesh my RVE with a FE-software?

Thank you in advance.

Best regards,
Mathieu

[louisepb]

Hi Mathieu,

Because of the way the meshing algorithm works the top surface of the domain is split into sections along the edges where the yarns cross. If, therefore, the yarns are close together then this will result in thin strips being generated. The resulting sections are then meshes using the Triangle software here http://www.cs.cmu.edu/~quake/triangle.html. The thin strips will inevitably result in small triangles.

At the moment the default quality switch is used which specifies a minimum angle of 20 degrees. If you are using a bundled version of TexGen then you won't be able to change this. If however you have built your own version then you could change the flag in BasicVolumes.cpp and set the minimum angle for the -q switch in the MeshProjectedAreas function.

Failing that you could try exporting as a STEP or IGES file and then mesh elsewhere.

Hope that helps,
Louise

[mat]

Hi Louise,

I am currently trying to install the non-bundled version of TexGen. When configuring the GUI module, I get an error (see the screenshot), which I didn't manage to solve until now.

Do you have a clue, what the problem can be?
Is the line "wxWidgets_CONFIG_EXECUTABLE" correct?

Thank you.

Regards,
Mathieu

[louisepb]

Hi Mathieu,

I'm not quite sure what you're trying to do here. By 'non-bundled version of TexGen' do you mean texgen-3.7.0? If so you should just be able to run the installer and run TexGen without the need to build it. It requires that you have Python 2.6 installed on your system.

If you've downloaded the source code from the repository and are building TexGen then, if you want to build the GUI, you need to have downloaded and built wxWidgets. The instructions are here http://texgen.sourceforge.net/index.php ... rom_Source

Hope that helps,
Louise

[mat]

Hi,

Yes I downloaded the source code, if I correctly understood what you wrote in your last post, I need to build a version of TexGen with the source code to be able to change the "BasicVolumes.cpp" file, is that right?

I already built wxWidgets and all other programs and libraries, and managed to configure most of the modules (excepted the GUI module).
I'll try to build wxWidgets once again, maybe I've done sometimes wrong during my first attempt.

Regards,
Mathieu

[louisepb]

Hi Mathieu,

Ok - that makes sense. Yes, you need to build TexGen if you want to change the volume mesh parameters.

I'm not sure what the wxWidgets_CONFIG_EXECUTABLE should be. I don't have this in my setup. The wxWidgets setup on my system looks like this:

CMake snippet.PNG (6.85 KiB) Viewed 13685 times

It looks like you're building in Windows - is that correct?

Let me know how you get on.

Louise

[louisepb]

Hi again Mathieu,

I've just taken a look at the CMake on my Linux partition and that does have an entry for wxWidgets_CONFIG_EXECUTABLE. It contains the path ending in wx-config rather than the actual file name.

I notice that your wxWidgets is in a gcc folder so I wonder if it's the difference between configuring for gcc and Visual Studio (I use gcc in Linux and VS in Windows)

Best regards,
Louise

[mat]

Hi Louise,

Thank you for the information. When I build wxWidgets with gcc, there's some errors. I'll try to install Visual Studio and build wxWidgets with it, it'll maybe be better then.

I'll keep you informed of my progress.

Best regards,
Mathieu

[louisepb]

Hi Mathieu,

I can build wxWidgets with gcc in Linux and everything works ok but I haven't tried it in Windows so I'm afraid don't really know if that's the issue or not. Hopefully everything will work ok in Visual Studio.

Louise

[mat]

Hi Louise,

I installed visual studio and things are working better now.
I finished the configuration with CMake, without becoming any errors.

When compiling the TexGen.sln file with Visual Studio, I still get three errors, which I can't get rid of.
Maybe you know how I can solve the problem. I join to the message some screenshot which can help you to understand what I've done.

Best regards,
Mathieu

[louisepb]

Hi Mathieu,

I don't understand the German but I think I can get the gist of what they're saying. It looks like you have a 32/64 bit conflict. You have built VTK using a 64-bit generator but have used Program Files(x86) as the install folder. This is where Windows 7 installs 32-bit applications. In the VS window you can see that it is looking for VTK in the Program Files folder (where 64-bit programs are installed). Try changing your VTK build installation folder to Program Files and see if that solves the problem. You've also got TexGen set to build into the x86 folder so that will need changing too.

Let me know how you get on,
Louise

[mat]

Hi again,

Indeed, I didn't remark that these paths were wrong!
The second error has been solved, still remain the two others. I'm trying to google it and find a solution for them.

Translations would be:
error MSB6006: "cmd.exe" exited with code 1
error LMK1181: input file "C:\Programm Files\VTK5.10.1\bin\bin\vtkGraphics.obj" can't be opened

What I noticed is that there is neither a bin\bin folder nor a vtkGraphics.obj file in the vtk folder. I continue my research to solve these 2 errors!

Thank you for your help!
Mathieu

[louisepb]

Hi Mathieu,

Try just putting the VTK_DIR as C:/Program Files/VTK5.10.1 - I think it adds the /bin itself which is why you've ended up with /bin/bin

Best regards,

Louise