topic Re: Shrink fit contact -anomaly - in Inventor Forum

Shrink fit contact -anomaly -

admaiora — Fri, 24 Nov 2017 14:14:00 GMT

Hi,

I have noted a discrepancy between 2016 and 2017 realeses.(stress analysis)

2016, no loads, shrink fit contact.

I can run the analysis and obtain contact pressure results.

2017, same assembly, same settings. no loads, shrink fit contact.

I can't run the analysis.

Re: Shrink fit contact -anomaly -

Xun.Zhang — Mon, 27 Nov 2017 05:23:32 GMT

Hi Admaiora,

Would you mind send me your dataset and I can help try in my end to understand it better.

Email: Xun.zhang@autodesk.com

Thanks!

Re: Shrink fit contact -anomaly -

admaiora — Mon, 27 Nov 2017 08:20:02 GMT

Hi Xun,

you will have the sane results with every assembly.

Anyway you will find 2 samples.

The Stress Analysis workflow:

- we want to analize contact pressure between two forced parts.

- parts has interferences (wanted)

- just use fixed and frictionless constraints

- no load needs to be added

- automatic contacts, then convert the only bonded in Shrink Fit/Sliding.

-Then run aanalysis

Until 2016 we can run analysis of this time (even if there are no loads)

With 2017, same models, same settings, same analysis, we can't run analysis because there are no loads.

Thank you Xun

Re: Shrink fit contact -anomaly -

karthur1 — Mon, 27 Nov 2017 14:19:50 GMT

I tried it in 2018 and it will not run. Get the same "No Load defined" error.

Re: Shrink fit contact -anomaly -

admaiora — Mon, 27 Nov 2017 14:23:12 GMT

Thank you @karthur1

to this end, the Shirk Fit Contact is useless for static contact pressure studies.

Re: Shrink fit contact -anomaly -

admaiora — Thu, 30 Nov 2017 10:07:57 GMT

Any updates?

Re: Shrink fit contact -anomaly -

kelly.young — Sat, 02 Dec 2017 00:54:14 GMT

@admaiora after investigating a bit, in the older version it states the error No load defined but still lets you click the Run button.

In the 2018 version the Run button is greyed out with these same settings.

I'm not sure if this was a conscious effort to eliminate allowing the simulation to be run without the load and was fixed, which in your case is now "broken" as far as your use and functionality.

I sent the issue to the development team so I'll see what I can find and report back.

Please select the Accept as Solution button if a post solves your issue or answers your question.

Re: Shrink fit contact -anomaly -

johnsonshiue — Sat, 02 Dec 2017 20:43:48 GMT

Hi Guys,

Indeed, there seems to be a behavioral change here. It is not clear to me why the change happened. I did try tricking the solver by adding a non-essential load (very small pressure like 0.0000001 MPa) and the solve did go through. But, I am not sure if the result is consistent with 2016 since I don't have access to the release at the moment. I will try it on Monday.

Many thanks!

Re: Shrink fit contact -anomaly -

johnsonshiue — Tue, 05 Dec 2017 00:25:02 GMT

Hi admaiora,

I just tried it on Inventor Pro 2016. I was not able to start a Simulation. Is it on Inventor FEA or it was on NASTRAN In-CAD?

Many thanks!

Re: Shrink fit contact -anomaly -

admaiora — Tue, 05 Dec 2017 12:17:47 GMT

Inventor FEA, Inv Pro 2016

Re: Shrink fit contact -anomaly -

johnsonshiue — Tue, 05 Dec 2017 19:16:01 GMT

Hi admaiora,

Then I cannot explain the behavior. On 2016, I am not able to start a Simulation without a load. Do you still have access to 2016?

Many thanks!

Re: Shrink fit contact -anomaly -

admaiora — Tue, 05 Dec 2017 19:37:28 GMT

Hi @johnsonshiue for your constant support!

Here as I always used this kind of contact:

Re: Shrink fit contact -anomaly -

kelly.young — Tue, 05 Dec 2017 19:40:02 GMT

@johnsonshiue here are the 2016 files I made real quick to test the setup, @admaiora can you verify this is how you want it?

It gives the No Load defined error but the Run box is not greyed out like in newer version. Hope that clears it up a bit.