bug in displacement?

[cnajafi]

after analysing my model, a component which was constraint on one side and the other side of that was resting on a V groove had most deformation.

But what results shows me is that my component deformed into other component instead of walking over it. is this a bug? So creO is not able to undrestand the boundaries?

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[danderson]

Hi Camron,

Do you have contacts defined between the 2 parts in question?
Most likely your model analysis setup is missing something.

Don

[cnajafi]

I defined constraint on one end but at the other end I didn't define anything. that ring should be a boundary or something?

[cnajafi]

So after some research I noticed that contact interface is only working for non-linear static analysis and in other cases they will be considered as free interface. I don't know why ptc programmed the software like that.

[mlindqvist]

Contact is a nonlinear phenomenon, so you want to include contacts, by definition you will need to run a non-linear analysis. This is not any different from any other software. A significant improvement came in Creo1 when you can combine several nonlinear phenomenon. Contact problems sometimes need to be combined with large deflection analysis, and this is now possible from Creo 1 and onwards...

[ptc-6362412]

In my experience, Creo has completely ignored tangential contact between a round a flat surface. Could that be an issue here?

[sdensberger]

Why do you say that?

[ptc-6362412]

The diagnostics window would indicate that it was ignored.

[346gnu]

There were a couple of problems here originally.

1. One analysis was a modal, the contact is ignored hence unexpected results.

2. The results scaling of the static contact study was a little enthusuastic and the components appeared to pass through each other.

[sdensberger]

"The results scaling of the static contact study was a little enthusuastic and the components appeared to pass through each other."

It's normal for the objects to slightly pass through one another in a contact analysis. Internally, contact is done using springs between the surfaces and the engine will iterate and adjust the spring stiffness to try and enforce the contact interface. However, it's impossible to prevent all penetration from happening, since doing so would require an spring with infinite stiffness.

[sdensberger]

Hmm, I'd need to see the model then. Mechanica can do tangential contact (like Hertz contact problems).