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Thermal stress with contact pairs

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Hi,

I'm having trouble with a simple thermal stress model (axisymmetric, time-dependent, COMSOL 5.1). The model has two cylindrical parts that contact each other on one face, starting at different temperatures. As heat flows between them, one will expand as it heats up and the other will contract as it cools. Since the contacting surfaces must be allowed to slide against one another as this happens, I am using Form Assembly with a Contact Pair at the interface. To model the heat transfer across the boundary, I am using a Pair Thermal Contact node in the Heat Transfer in Solids module. When I try to solve, I encounter the following error:

Failed to find consistent initial values.
Last time step is not converged.
- Feature: Time-Dependent Solver 1 (sol1/t1)

If I change from Form Assembly to Form Union and disable the Pair Thermal Contact, the model solves just fine, so the problem seems to be related to the presence of the contact pair. Has anyone encountered this type of issue? (I'd upload the model but the uploader is telling me that the .mph extension is not allowed.)

Thanks!
Phil

2 Replies Last Post 2017年11月23日 GMT-5 06:18
Henrik Sönnerlind COMSOL Employee

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Posted: 7 years ago 2017年6月9日 GMT-4 03:47
Hi,

You have not mentioned how you have set up the structural part of the contact. Penalty method? Friction or not?

Without that info, it will be difficult to have any suggestions.

Regards,
Henrik
Hi, You have not mentioned how you have set up the structural part of the contact. Penalty method? Friction or not? Without that info, it will be difficult to have any suggestions. Regards, Henrik

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Posted: 6 years ago 2017年11月23日 GMT-5 06:18

Good morning,

I am trying to do a similar analysis. I have three parts which are heated to a certain temperature and let cool to environmental temperature, so they are compressed together. The two contacts are fixed together by friction node.

I am trying to do a time dependent study to calculate the contact pressure between the parts, but this is not my field of expertise, so I am facing problems in making the study running.

Would you be able to help with the few information I shared?

If you require any more, please let me know and I will try to find out some.

Thanks in advance,

Pavlos.

Good morning, I am trying to do a similar analysis. I have three parts which are heated to a certain temperature and let cool to environmental temperature, so they are compressed together. The two contacts are fixed together by friction node. I am trying to do a time dependent study to calculate the contact pressure between the parts, but this is not my field of expertise, so I am facing problems in making the study running. Would you be able to help with the few information I shared? If you require any more, please let me know and I will try to find out some. Thanks in advance, Pavlos.

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