ERROR 320
Altair EmployeeHello,
I'm trying to run a topology optimization on a 3D volume meshed with tetra elements.
the objective is to minimize the Weighted Compliance.
The responses I've chosen are :
- weighted compliance
- Vol Frac
the constraints are :
- VolFrac <0.1
- max stress < 870 MPa (via STRESS input in the DTPL card).
I get the following error message:
' *** ERROR # 320 ***
Static load case 1 has prescribed displacements.
The combination of global stress constraints and prescribed displacements
is not meaningful. Optimization cannot be performed.'
I hardly see why it is not meaningful to use global stress constraints with SPCD...
does anybody have a solution?
Note: the SPCD is applied on a single node which is connected to the volume using a RBE2. Do I have to remove the area close to the RBE2 from the design volume?
Find more posts tagged with
Hi
could you please tell me how you solved the problem? I'm getting the same error but I think I don't have any prescribed displacements in my model. I'm also using weighted compliance and vol Frac as responses. The optimization is running but as soon as I set a max stress I'm getting this error.
Altair EmployeeHi,
Try withtout stress. Infact, stress constraint is not recommended.
There are few recommended optimization problem setups available in OptiStruct FAQs. Go through that and setup your problem accordingly /emoticons/default_smile.png' srcset='/emoticons/smile@2x.png 2x' title=':)' width='20'>
Sorry, it is clearly written in the User Guide: 'Stress constraints may not be used when enforced displacements are present in the model.'
I have to find another way to 'express' the optimization problem without using stress constraints.