Export command for sphere packings from YADE to FEM packages like ABAQUS

Hello,

I can not answer to your precise question about export function, but for your question : "how the sphere particles deform", it is very simple : they do not deform at all !

They can interpenetrate into each other, but the shapes do not change. Did I get your point ?

Hello Manu,

as Jerome already said, there is no deformation of particles. Didn't you
meant the displacement of particles? if so, there are ways to export them.

Concerning the errors of export.textExt format, could you please send a
short script reproducing the error and also the actual error you get? it
will help us to solve your problem or to correct a mistakes in source code
if there are some.

I do not know Abaqus very well, but what would you like to achieve by
exporting geometry (and also what you exactly mean by "geometry")? have
abaqus some features to handle spherical particles? It could be possible to
export facets (triangles) as tirangular finite elements, but this feature
is not implemented yet (according to my knowledge).

There is also no automatic meshing in Yade, althought facets (triangles)
can be imported from some external files or can be created using gts
module. The creating of spheres (which is automatized) we call packing
rather than meshing (as there is no real mesh), did you mean this?

good luck and do not hesitate to ask again :-)

Jan

2012/7/17 Manu <email address hidden>

> New question #203385 on Yade:
> https://answers.launchpad.net/yade/+question/203385
>
> I am a new user of YADE. I am trying to export the sphere packings from
> YADE to a finite element solver like ABAQUS to understand how the sphere
> particles deform. However, I am not sure of the commands I need to use to
> export the sphere packings from YADE to ABAQUS.
>
> When I use a command like:
>
> export.textExt(filename, format=’x_y_z_r’)
>
> from the YADE python file I get errors. I don't know if there is an
> example in YADE manual on how I can export the YADE geometry into ABAQUS
> for meshing. The YADE documentation files don't have suitable help files in
> this regard. If you can guide me to a suitable example of the command I
> should use to export the model to ABAQUS from YADE it would be of great
> help for me to get started.
>
> Also if I could get some help files on meshing in YADE it would be of
> great help to me.
>
> Thanks a lot
> Manu
>
> --
> You received this question notification because you are a member of
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HI Jan

Thank you for the feedback. I am actually interested in exporting the
particles to ABAQUS, so that I can understand the deformation and
non-linear behaviour of the particles (metal powder) during compaction.

If you can guide me to what command I can use, that would be of great help.

Thanks
Manu

On 17 July 2012 21:25, Jan Stránský <email address hidden>wrote:

> Question #203385 on Yade changed:
> https://answers.launchpad.net/yade/+question/203385
>
> Jan Stránský proposed the following answer:
> Hello Manu,
>
> as Jerome already said, there is no deformation of particles. Didn't you
> meant the displacement of particles? if so, there are ways to export them.
>
> Concerning the errors of export.textExt format, could you please send a
> short script reproducing the error and also the actual error you get? it
> will help us to solve your problem or to correct a mistakes in source code
> if there are some.
>
> I do not know Abaqus very well, but what would you like to achieve by
> exporting geometry (and also what you exactly mean by "geometry")? have
> abaqus some features to handle spherical particles? It could be possible to
> export facets (triangles) as tirangular finite elements, but this feature
> is not implemented yet (according to my knowledge).
>
> There is also no automatic meshing in Yade, althought facets (triangles)
> can be imported from some external files or can be created using gts
> module. The creating of spheres (which is automatized) we call packing
> rather than meshing (as there is no real mesh), did you mean this?
>
> good luck and do not hesitate to ask again :-)
>
> Jan
>
>
>
> 2012/7/17 Manu <email address hidden>
>
> > New question #203385 on Yade:
> > https://answers.launchpad.net/yade/+question/203385
> >
> > I am a new user of YADE. I am trying to export the sphere packings from
> > YADE to a finite element solver like ABAQUS to understand how the sphere
> > particles deform. However, I am not sure of the commands I need to use to
> > export the sphere packings from YADE to ABAQUS.
> >
> > When I use a command like:
> >
> > export.textExt(filename, format=’x_y_z_r’)
> >
> > from the YADE python file I get errors. I don't know if there is an
> > example in YADE manual on how I can export the YADE geometry into ABAQUS
> > for meshing. The YADE documentation files don't have suitable help files
> in
> > this regard. If you can guide me to a suitable example of the command I
> > should use to export the model to ABAQUS from YADE it would be of great
> > help for me to get started.
> >
> > Also if I could get some help files on meshing in YADE it would be of
> > great help to me.
> >
> > Thanks a lot
> > Manu
> >
> > --
> > You received this question notification because you are a member of
> > yade-users, which is an answer contact for Yade.
> >
> > _______________________________________________
> > Mailing list: https://launchpad.net/~yade-users
> > Post to : <email address hidden>
> > Unsubscribe : https://launchpad.net/~yade-users
> > More help : https://help.launchpad.net/ListHelp
> >
>
> --
> You received this question notification because you are a member of
> yade-users, which is an answer contact for Yade.
>
> _______________________________________________
> Mailing list: https://launchpad.net/~yade-users
> Post to : <email address hidden>
> Unsubscribe : https://launchpad.net/~yade-users
> More help : https://help.launchpad.net/ListHelp
>

Hey,

Just to be sure about what you want to do. Do you actually want to export positions and radii of particles into a text file so that you can import it into ABAQUS? If yes, the export function should work, but you have to import the export module first (I know, the combination import export can sound a bit weird). In your terminal (with a model previously launched, of course!), try to type:

from yade import export
export.text('spheres')

That should do the trick.

You are probably aware of those works from B Harthong and JF Jerier on the subject:

http://www.sciencedirect.com/science/article/pii/S0032591010004481
http://www.sciencedirect.com/science/article/pii/S0020740312001014
http://www.sciencedirect.com/science/article/pii/S0020768309002054

Cheers

Luc