Fatigue Topology optimization

Altair Forum User

Hello,

 

I am trying to do a topology optimization on an automotive part for fatigue damage. The process I am following is 

1. Define the fatigue damage as response using the fatigue loadstep created.
2. Define design constraint as damagevariable<1.
3. Create a response for volume fraction.
4. Define objective function as min volume fraction.
5. Create a topology optimization desvar with damage less than 1 in parameter section.

 

It however gives an error :

Fatigue responses are applied to property 688188 which belongs to a
 topology or free-size domain. For fatigue-constrained topology or
 free-size optimization, please use the FATIGUE option on the design
 variable definition card.

 

If someone is aware of the problem please help me.

Altair Forum User

Hi Swapnil,

 

In Topology panel you can define Fatigue optimization parameters. Please use that instead. 

Altair Forum User

Hi Prakash,

 

Thank you for the swift response. I tried giving a fatigue optimization parameter in the topology panel and volume fraction as the design objective. But I cannot constraint the volume fraction then as it is the only objective left. Also if I use this approach will the solver add material in the design regions to reduce the damage value even if left unbounded.

 

Thanks,

Swapnil

Altair Forum User

Hi Swapnil,

 

Do you want to increase the mass/volume of the component?

 

In such a case you can maximize mass/volume.