Free-size fe-reanalysis

Altair Forum User

Hello,

 

 

 

my question is related to a free-size optimization of a metal sheet done with shell-elements. 

 

The model is simple, because it is not for application, but to compare it with the results of a SIMP-method topology optimization.

 

So there are no manufactoring restrictions.

 

 

 

Objective: min compliance

 

Restriction: volume max 30% of designspace

 

Base thickness: 0.0

 

 

 

So the result needs to be interpreted, because there are void areas after optimization.

 

I would like to do this using Isometric lines depending on thickness in Hyperview

 

and then use OSSmooth for fe-reanalysis with the threshold-value I got from Hyperview.

 

 

 

But when I do this, it seems like I can not get the thickness-distribution of the optimized design

 

for the fe-reanlaysis.

 

Can you tell me a way to solve it?

 

Altair Forum User

Hello Philipp,

thank you for your request and detailed description. In order to perform an FEM re-analysis with Shells, you should prefer importing a 'thickness' file over Ossmooth. The thickness file for your optimized element thicknesses will be written automatically by the solver and can be imported in HyperMesh via Import - Solver Deck. When importing the thickness file, make sure that you have the 'fe overwrite' option active. By importing, all element thicknesses will be overwritten and replaced with the optimized thickness.  Here is a flash video that shows how to do so: http://screencast.com/t/NFXfqvsq6

 

In case you want to delete certain elements from your part (e.g. all elements with t < 1,0 mm), you can run a command file after optimization and then delete elements by thickness. See here for a description of the steps:http://screencast.com/t/HoVGhbGX

 

Best Regards

 Jan

 

Mathilde.L

Altair Forum User said:

Hello Philipp,

thank you for your request and detailed description. In order to perform an FEM re-analysis with Shells, you should prefer importing a 'thickness' file over Ossmooth. The thickness file for your optimized element thicknesses will be written automatically by the solver and can be imported in HyperMesh via Import - Solver Deck. When importing the thickness file, make sure that you have the 'fe overwrite' option active. By importing, all element thicknesses will be overwritten and replaced with the optimized thickness.  Here is a flash video that shows how to do so: http://screencast.com/t/NFXfqvsq6

 

In case you want to delete certain elements from your part (e.g. all elements with t < 1,0 mm), you can run a command file after optimization and then delete elements by thickness. See here for a description of the steps:http://screencast.com/t/HoVGhbGX

 

Best Regards

 Jan

 

Hello,

I would like to do a FEA reanalysis after a free size optimization. Can you tell me how I can have the "thickness file" to import it over Ossmooth ? 

Because when I am doing the Ossmooth with my fem file, all the elements have the same thickness...

And the videos are no longer available, that is why I am asking ! 

 

Thank you very much for your help.

Kind regards,

Mathilde

Mathilde.L

Hello, 

 

In the case you want to visualize the thickness in Hyperworks, you do not have to do an Ossmooth.

You can directly import your fem file into Hyperworks and then import on it (overwrite) your thickness file (.fsthick). Normally you should be able to see the thickness of your elements.

 

Kind regards,

Mathilde

Klaus W.

Hello,

I'm also having issues with importing the results from the optimization run (freeSize) for further analysis. 

The information in the *.fsthick file is not complete:

$
$ CQUAD4 elements for property 80000282
$
$
$ CTRIA3 elements for property 80000282
$
$
$ CQUAD4 elements for property 80000285
$
$

 

Or how do I import the information contained in the *.sh file?

Reading the *.sh file with OSSmooth changes the mesh, what I do no want to.

Is there any tutorial available? Or is the video "http://screencast.com/t/NFXfqvsq6" available on a Altair server? I'm not allowed to access this link.

 

Thanks,

Klaus

Mathilde.L

Klaus W. said:

Hello,

I'm also having issues with importing the results from the optimization run (freeSize) for further analysis. 

The information in the *.fsthick file is not complete:

$
$ CQUAD4 elements for property 80000282
$
$
$ CTRIA3 elements for property 80000282
$
$
$ CQUAD4 elements for property 80000285
$
$

 

Or how do I import the information contained in the *.sh file?

Reading the *.sh file with OSSmooth changes the mesh, what I do no want to.

Is there any tutorial available? Or is the video "http://screencast.com/t/NFXfqvsq6" available on a Altair server? I'm not allowed to access this link.

 

Thanks,

Klaus

Hello Klaus,

 

Why your *.fsthick file is not complete ? Have you assign a property to all your elements ?

Can you maybe share your *.fem and *.fsthick file ?

I don't think it is possible to import your *.sh file into Hyperworks without using OSSmooth. Or I didn't find it.

 

The only solution I found to visualize the thickness of the elements and to do further analysis on the result of the free size optimization, is to import first your *.fem file and then to import on the same model your *.fsthick file. Don't forget to select "overwrite" when you import the *.fsthick file.

 

I hope it can help,

Mathilde