CATIA FEM: Deformable Contact Area

Simulation Generality
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Hi all

 

I'm on Catia v5 which I use to model my mechanism for finite element analysis. I would like to model the support of two soft objects against each other and whose contact area will strongly evolve with the effort.

A little paint diagram (amateurs will appreciate the comic without MS in bad taste):

I never bothered with this problem because most of the time I was using very rigid materials. Indeed everything deforms, but catia does not seem to actualize the collision with the deformed elements. Basically, only the initial surface is deformed, and I would like this to take into account the new contacts that are created between the two parts.

I've seen articles that talk about collisions but it doesn't seem to be applicable to finite elements. Is there a method for catia to take this into account or hacks?

Thank you in advance for your answers,

Kind regards.

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The image is displayed incorrectly (and the edit function was not found): http://img15.hostingpics.net/pics/821208probleme.png

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Hello, indeed I don't think it's possible. We can then imagine several steps where the contact surface is modified according to the deformations resulting from the previous calculation.

Editing: we're talking about a deformable virtual part on page 13, but I don't think it answers your problem:

http://www.lynkoa.com/sites/default/files/questions/answer/03/03/2015/analyse_catia_v5.pdf

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at the sight of your image

We have the impression that the deformation is identical on the 2 structures

absolutely unreal case between a flat surface and a sphere

In this case, you can say that you have a balance of force

tests may be to create a spherical volume in a flexible material

to make a parallepipedic plane volume of the same flexible material

and see how far the balance of power will be and deduce from it

the thickness or material of the parallepipedic planar volume

and visualize the deformation

I think that the most important force will be in any case at the pole of the sphere  , the point of meeting with the soft solid

and will diminish as it penetrates the parallepipid

from there to deduce a homogeneous deformation of the 2 bodies I am like the pit ;-)

@+ ;-))

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Hello

Not sure that you will get a convincing result with Catia because, apart from some specific software, this type of calculation that generates large displacements is not taken into account.

If the goal is just to know the contact surface you can get out of it analytically using the formulas of the Hertz pressure (example attached).


contact_hertz.pdf
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Ah, it's true that my diagram is quite ugly!

Thanks for the leads, I'll try all that. (no big deal if it ends up with a jacky-tuning method to do it with Catia.)   Taking up the ideas that have been stated, I imagine that I can do a kind of "step by step" by regaining a new contact area with the interference function, once my two solids are deformed, look for equilibrium with a stopping criterion.

On the other hand, can we "export" the deformed geometry as a part in its own right, to reuse it in an assembly and thus determine the intersection of the parts? (or this function already exists in Analysis, but I haven't seen it)

After if it works, can we automate a script to do it step by step with Catia? (so I leave the PC running at night)

For the analytical way, I prefer to try it as a last resort, because my shapes are uglier than a simple sphere/plane. But thank you for the link, I'll go and see if there are any ideas to get out of it.

I'll keep you informed of where these leads lead.

(NB: you absolutely have to choose a "best answer", even if the solution at the end is a mixture of various ideas?)

Yours truly, thank you again!

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You. You can also write down the answers that help you define your approach for your study 

and choose the answer that helps you solve your problem or approach to solve your problem

@+;-))

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Maybe choose a better answer here and open a new question? Because in the end these new questions are very different, but interesting too, so deserve one or more questions.

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