Learning Forum

[Rameez_ul_Haq]

So, I was conducting a topology optimization in ANSYS for a structure, but there was presence of some singularities in the structure already and after conducting the optimization, those regions were kept. However, since its a singularity, I know that high amount of stress is not going to occur there. So how to deal with this issue?

[I know one option is to replace the singularity regions with a fillet but the static structural analysis has already been conducted and replacing these singular geometric features with a fillet will require a re-analysis which will take time].

[1shan]

If the singularity regions don't have high stresses why is it a problem? You could simply specify the optimization region away from these singularities or use local constraints over a specified region so that only important areas are considered and the rest are excluded.
Regards Ishan.

[Rameez_ul_Haq]

,I had an ACP linked to a static structural. The static structural had composite surface bodies as well as solid metal bodies. When I tried conducting topology optimization, the solver didn't start giving as error, "The imported layered section is not allowered in the current analysis". Although I selected the solid metal bodies onto which I wanted the topology optimization to happen. Does this mean that even if only the composite surface body is a part of the model but included in the bodies of which I want the topology optimization, still I cannot run the solver?
Or is there any way I can make the solver to begin?

[Rameez_ul_Haq]

,and also, why doesn't the topology optimization support the solution with Large Deflection turned ON?

[Rameez_ul_Haq]

,can I have your views on this please?

[Rameez_ul_Haq]

,can you please tell me something about this? A general answer to the question that I asked?

[1shan]

Sorry for the delay. Here are the limitations to Density based topology optimization. I haven't tried it but since the limitations state that imported plies are not supported, I assume you cannot include them in the analysis even if they are not included inside the optimization region. Not sure but you can try suppressing the composite body, add imported displacement at the composite-solid body connection and proceed with optimization.
I am not an expert in optimization algorithms but I know that there are several problems associated with density based optimization of structures with geometric non-linearity, like the tangent stiffness of elements with low density becomes negative during the optimization process. There are several research articles which propose techniques to handle non-linearity in topology optimization. Please have a look if you are interested.
Regards Ishan.

[Rameez_ul_Haq]

thank you for replying :)
I usually use the imported displacements when I am doing submodelling of a structure. However, if the composite has a contact connection with a solid body, and some external forces are already applied on the solid body then if I try to import the displacements at that connection, it would basically mean that I am inputting an external thing. However, the displacements, when there is a connection, are generated automatically due to the nature of the overall structure. If I change the nature of it (by removing the composite) and input manually a displacments at those connections, then basically I am forcing the faces to displace by those values. These become external. Whereas in the former case, it is what it should be (without any interference) naturally.
I hope you got what I was trying to convey. I am just concerned that importing the displacements could create a difference in the stresses of the overall structure since they are externally applied onto the faces.