Optistruct- material turns 'foamy' and disappears

Altair Forum User

Hi all,

 

I am currently using Optistruct to optimize the geometry for a bellcrank for a Formula Student suspension system. For optimization purposes, I modelled the worst case scenario (i.e. bellcrank blocks and all in-plane forces go through it). As constraints, I constrained the X-movement of the shock point (top hole) and only allowed Z rotation at the hinge point, applying a load (split into X and Y components) at the third point (bottom hole). Applied 'Volume Fraction' as response as well as an upper stress limit and minimum volume as the objective. As I run the optimization,the material turns 'foamy' and disappears completely as I change the ISO value (i.e. it does not give me any geometry, as the material just disappears as a whole).

 

Has anyone experienced this issue before or have any ideas how this could be fixed?

 

Thanks!

 

Adam

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Altair Forum User

Hi @adamk95

There could be several reasons for this behavior.

 

It could be because of material, optimization setup, etc...

Can you share the model?

 

Use this File Transfer LINK

Altair Forum User

Hi @adamk95

 

Suggestion: Can you move the elements around the bolt area to non-design space and check if it gives any reasonable results?

 

I can see all the elements are used for optimization. Move the elements around the bolt/BCs area to non-design space and try again.