Learning Forum

[VanHa]

Hello,

I downloaded archived file from innovation course platform

Course name: Prevent Rigid Body Motion in Contact

Lesson 2: How To Utilize Contact Stabilization Damping Correctly

File name: UtilizeContactStabilizationDampingCorrectly.zip

I rerun without any modification the "Complete" file, the Stabilization Energy is higher than Stiffness Energy. I also tried to follow steps in the video with "Starting" file, but the same output Stabilization Energy higher than Stiffness Energy. Below pictures are showing difference.

Question: Is there any wrong with the file ? I'm using student version, 2021 R2

[Erik Kostson]

Hi
this video is from 2020 so 2020 R1 wsa used or R2 - try using the same version and see if you get the same (you are using 2021 R2), and of course have exactly the same set up.

All the best

Erik

[VanHa]

Hello Can you tell me how to download student version 2020 R1 ? I checked on the website, but there is only version 2021 R2 and cannot find lower version. See below picture
Thanks

[Erik Kostson]

Hi Perhaps it is not possible to download such an old version -
Anyway what I believe has happened is that there have been some changes in the contact stabilization damping calculations which have altered the behaviour from 2020 R1 and to 2021 R2.

Not much that can be done here - most important:
in general though the main message is that this contact stabilization damping should be small compared to the elastic energy (stiffness), so that is the message.

For this particular example it will help to put in an apdl command snippet under the contact object in your tree (so right mouse button click on the contact object and insert commands) , that makes it use only damping initially when it is needed and not through out the analysis as it is by default in WB/mech 2021 R2 (so damping energy will be much less than before where it is always used throughout all of the analysis).

Apdl command Snippet is:

keyopt,cid,15,0

All the best

Erik

[VanHa]

Hi Erik
Thank you