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Problem with Loading and Vibration Response of Stacked Plates

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I want to test various loading conditions and the vibration response of a metal plate on top of a rubber pad. I have set up a model with the following conditions, but it produces errors and fails to find a solution.

Overall Setup:

• 3D model

• metal plate on top of a rubber pad

• force applied on top surface of metal plate

Desired Results:

• Plot displacement

• Plot stress

Current setup and issues:

Before testing a frequency-driven loading force, I wanted to test static loading to make sure there were no issues in the setup. I’m not sure what isn’t working, since I think I’ve constrained everything to only allow movement in the vertical direction and I’m looking for stress and displacement.

Geometry: Two blocks created, one on top of the other. Assembly formed with contact pair created at midplane for block contact. Materials selected for each block and required properties applied. (See attached image)

Physics: Solid Mechanics physics was selected. Boundary load node applied on top surface of top block. Contact pair node applied to contact pair between the blocks. Fixed face node applied to bottom face of bottom block. Roller node applied to sides of top block.

Study: Stationary study was selected.

Error during computation:

• Failed to find a solution.

• Maximum number of dogleg iterations reached.

• There was an error message from the linear solver.

• The relative residual (0.58) is greater than the relative tolerance.

• Returned solution is not converged.

• Not all parameter steps returned.



2 Replies Last Post 2020/07/08 17:57 GMT-4
Edgar J. Kaiser Certified Consultant

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Posted: 4 years ago 2020/07/08 16:48 GMT-4

Hi,

the contact is the culprit. If both plates are intended to remain permanently attached to each other you don't need it. Comsol takes care of continuity. If you need the contact, this is where you need to refine.

Cheers Edgar

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Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Hi, the contact is the culprit. If both plates are intended to remain permanently attached to each other you don't need it. Comsol takes care of continuity. If you need the contact, this is where you need to refine. Cheers Edgar

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Posted: 4 years ago 2020/07/08 17:57 GMT-4

Hi Edgar,

Thank you for the advice. Changing the assembly to a union and removing the contact fixed the issues.

Regards, Kauri

Hi Edgar, Thank you for the advice. Changing the assembly to a union and removing the contact fixed the issues. Regards, Kauri

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