Ensuring support of non-design regions in topology optimization

Sezek_O

Hello,

I want to run a topology optimization (TO) which is setted up in SIMLab 2024. For TO i use following seetings:

Design Space constraint:

• minimum thickness 6mm
• Overhanging Constraint 45deg
• angle tolerance 90deg
• distance tolerance 1mm

Response constraint:

• massFraction —> Upper Limit 0.6
• Response —> minimize Static comliance weighted across all subcases

Here the problem now: When I run the simulation the result is not printable, because the non-design-space will have overhangs, because the overhangig constraint is only connected to the design space.

I tried following approach which I did find in an Altair Whitepaper:

the non-design space is included in the design-space and an
additional volume fraction constraint is added for the region which is intended as non-design
space. This volume fraction is set to 1.0 which ensures that the region is filled with material
(making it a de-facto non-design region)

I tried now following boundary conditions with the inlcuded non-design-space:

Design Space constraint:

• minimum thickness 6mm
• Overhanging Constraint 45deg
• angle tolerance 90deg
• distance tolerance 1mm

Response constraint:

• massFraction —> Upper Limit 0.3(Only on the design-space body)
• VolumeFraction —> Lower Limit 1 (only on the non-design-space body)
• Response —> minimize Static comliance weighted across all subcases

Still it is not working. Do you have maybe some more experience?

Adriano_Koga

could you share a few images showing how are your boundary contitions and giving a few more details? or at least some schematics?

And what kind of results you're getting in the end…

Sezek_O

Hello Mr. Koga,

I will attach some screenshots and a schematics of the results.

bc_total.PNG

response_massfraction.PNG

response_volumefraction.PNG

response_static_compliance.PNG

topology_design_space.PNG

response_constraint_volume.PNG

response_constraint_mass.PNG

design_space_constraint.PNG

optimization_objektiv.PNG

Altair schematics Topology optimization results.pdf

screenshot_of_the_result.PNG

Masses:
Design_Space: 0.883kg
Non_design_space: 0.569kg

DTPL-Card.PNG

Do you need further information?

Sadly, I am not able to share detailed screenshots of the models due to confidential rules. Only if I can send you an E-Mail, I can provide you the data or the model.

Sezek_O

https://community.altair.com/discussion/comment/190517#Comment_190517

Hello Mr. Kuga,

below I uploaded some further information. Sadly, I did not saw the "Reply"-Function.

BR
Okan