Converting a 2D-axisymmetric model to a 3D equivalent model? 1

[Yunus9696]

Hello everyone
Hope you are fine.

It is conventional to simplify a 3D model to a 2D-axisymmetric equivalent model for the sake of simplicity.
the question here is if a 2D-axisymmetric model could be converted to a 3D equivalent model?

For example, you have done your 2D-axisymmetric simulation in which material properties change step by step and now you want to load it in a way that is not possible in an axisymmetric medium. So could you convert it to a 3D equivalent model in a valid way?

Thanks for your comments,
Kind regards,
Yunus.

 

[FEA way]

In fact, Abaqus has a feature that allows you to generate a 3D model from 2D axisymmetric one. This functionality is called symmetric model generation. Abaqus also offers some non-standard elements that can be used when the geometry is axisymmetric but loading is not - CAXA elements. Cylindrical elements (represented in 3D but much more computationally efficient than regular solid elements for axisymmetric structures) could also be helpful in your case.

 

[Yunus9696]

Thanks FEA way for your great clear responses.

I just checked them out and found that they cannot undergo twist (or torque).
I have a 3 step simulation in which a torque is applied on the model in the 2nd step an an axial load in the 3rd step.
And the material properties change due to the loads applied.

Once the simulation is done, I want to apply a (non-axisymmetric) load to my model and measure the deflection to validate my results against the analogous experimental results.

Is it reasonable to change the element type between step 2 and 3 or after the step 3 to be able to apply the non-axisymmetric load to the model?
Or any better way exists?

 

[FEA way]

Abaqus offers also CGAX elements which are axisymmetric but support torsion. They might be a good choice in your case. Otherwise, you could try using the aforementioned cylindrical elements (CCL).

 

[Yunus9696]

Thanks FEA way for your tip, but the torsion part of the simulation is done using CGAX elements, now I want to apply a point load perpendicular to the axis of the rotation of the axisymmetric model to see its deflection.
This cannot be done in the axisymmetric model as far as I know.
So it occurred to me if I could map my axisymmetric geometry and material properties to a 3D model so I could apply the non-axisymmetric load and measure the deflection.

My question is that if this method is reasonable and if yes, how could I implement it?

Regards,
Yunus.

 

[FEA way]

In such a case you can use the symmetric model generation technique that I've mentioned in the first reply. One of its features is revolving an axisymmetric model to create a 3D model. It's even possible to transfer the results from the axisymmetric model to 3D one if needed (this is called symmetric results transfer). These tools are fully described in the documentation and their use only requires specifying proper keywords.

 

[Yunus9696]

Oh I thought you were talking about just revolving the model in visualization tab to see the 3D view of the 2D axisymmetric model.

Now I got your point, thanks for the great tip. This will do the trick I guess.

Kind regards,
Yunus.