Topology Optimization Shape Constraints

[sbasude]

Hello,
I want to use the topology optimization feature in my static loading case. However, I would like the program to replace material properties for elements that take extra loading with a special cement, and I would also like these areas of material replacement to be of a certain geometry (thin, curved rods running through my models). Is there a way to do this?

 

[FEA way]

I'm afraid that it's not possible. Topology optimization algorithm changes the density (it's a design variable) of elements from initial model and couples the stiffness of each element with density to satisfy both objective function (minimization or maximization of some variable such as strain energy) and constraints (for example 60% reduction of initial mass). Removal of elements is done in such way that selected elements are given very low density and stiffness so that they don't contribute to the overall structural response of the model. In addition you can define constraints such as frozen regions (no material removal in selected area), demold control, member size restriction and enforced symmetry. Thus you can change the goal of optimization and apply constraints/restrictions on the optimization procedure that it has to take into account but you can't change the algorithm itself. Tosca doesn't let users go that far into its solver.

 

[sbasude]

Thanks for your reply.
Hm... I believe the process is called multimaterial optimization. You should be able to set parameters and constraints on the amount (volume or mass) of the other material and the simulation is supposed to determine the best placement for those elements. Would you happen to know if this is available in either Tosca or Isight?

 

[FEA way]

From what I know this is not possible in Tosca. Isight is used for parametric optimization, it can't perform topology optimization at all so it's not an option too. You will need some special software that allows users to go deeper into its solver capabilities.