Permissible values for thickness in Topology optimization

rzmehdipour

Hi there,

 

I wanted to know if it's possible to define thickness steps when performing topology optimization using Optistruct. For example assume there is a body of PSHELL elements, Initial thickness is 10 and base thickness is 2.5 and between these two values only 6 is permissible. Or in another case only 8.5 and 2.5 are possible for final part. How can I go with this kind of problems? The real problem is to decrease some deflections of sheet metal parts by adding welded patches so thickness in different regions can not be any value. For example if initial thickness is 2.5 mm then I want to improve strength by only welding some 6 mm thickness patches to it so optimization output must be only 2.5 and 8.5 mm thickness.

 

Please let me know if my question is not clear.

 

Thanks in advance.

Simon Križnik

Hi,

 

try this approach:

• mesh the non-design component and assign 2.5mm thickness
• duplicate the elements into the design component, equivalence nodes (F3) and assign 6mm thickness
• set up topology optimization referencing the design component with 0 base thickness
• to get distinct element densities increase the analysis>optimization>opti control>DISCRETE=2 or 3

Optionally, after interpreting topology optimization results into patches you could perform size optimization to get discrete thickness (DDVAL).