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[achen87]

Hi:

I create a 2D mesh geometry in ansys workbench and export it into a Nastran file.

However, when I import it into other software like lsdyna, I only get nodes but not elements.

Does anyone have this issue and know how to fix it? Thank you!

[Aniket]

can you explain your process in more details?

-Aniket

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[achen87]

So I drew a rectangular shape in ansys and created a mesh. Then I use the export to nastran file feature in ansys and get a file. Then I use the import nastran file feature in lsdyna and get the figure with dots, meaning only the node data is being read but not the elements data. 

[Ram Gopisetti]

Hi, 

Check the following link 

https://www.dynasupport.com/howtos/general/how-to-read-nastran-bulk-data-files

https://github.com/SteveDoyle2/pyNastran/commit/498dd4c60dcc3ec1bfbc78d80e9a2f63b9a34c92

Cheers Ram 

[achen87]

When I use COMSOL to create the meshing and the nastran file, I am able to get the element data in lsdyna. Therefore, I think the issue maybe coming from Ansys exporting the meshing? 

[peteroznewman]

Does LS-DYNA require linear elements?

Ansys Mechanical creates quadratic elements by default. In the Mesh details window, set the Element Order to Linear then Clear Generated Data and remesh. Export the Nastran file. Does that come into LS-DYNA now?

[achen87]

Right now, I have the following error message: 

[Aniket]

As indicated by error, you have a body with zero thickness, if you observe carefully, there is a question mark in front of the surface body. If you select it you can see the thickness highlighted in yellow in the details view. Provide appropriate thickness and retry.

-Aniket

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[achen87]

I am interested in creating a 2D meshing file. Your method works for 3D.

Do you know how to create and export a 2D mesh file? Mainly the exporting part. Thank you!

[achen87]

 

looks like linear works for 3D geometry. Thank you