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contact problem with coupled structural and thermal multiphysics

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Hi,

I am trying to simulate a 3D problem which involves structural and thermal multiphysics. I would like to create 2 concentric cylinders which the inner cylinder expands more than the outer cylinder when heated. Right now if I do not specify the contact pair, the inner cylinder will simply go into the outer cylinder after the simulation which is unreal.

If I try to include contact pair, the simulation cannot be solved and the following error message will appear:

"Error: 7220
All variables solved for must be treated in at least one segregated solver step."

I would really appreciate it if anyone has experienced this and knows how to solve it.

Thank you,

John

5 Replies Last Post 09.04.2011, 12:00 GMT-4

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Posted: 10 years ago 16.04.2010, 06:47 GMT-4
Look at the solvermanager. All variables, which have to be solved, are listed there. Just include them for the solving-process in one step of the segregated solver by opening a new step.

The problem is: Comsol can't solve contact problems time-dependent! You have to change certain settings in the model in order to use time-dependent solving. There is an example-model, you can find somewhere in the discussion forum.

Look at the solvermanager. All variables, which have to be solved, are listed there. Just include them for the solving-process in one step of the segregated solver by opening a new step. The problem is: Comsol can't solve contact problems time-dependent! You have to change certain settings in the model in order to use time-dependent solving. There is an example-model, you can find somewhere in the discussion forum.

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Posted: 9 years ago 22.03.2011, 23:55 GMT-4
Hello!
I have the same problem, too. I don't know that if you had solved the problem, could you give me same advice about the error?
My model is also coupled structual and thermal multiphysics with friction, when I use stationary slover ,the nonlinear solver has no convergence. So i tried the time-dependent solver algorithm, it occurs error 7220.
In the HELP file, it says: the solve contact problems,use the augmented Lagrangian method. I think the augmented Lagrangian method is Stationary solver, what I should do with the time-dependent solver?
Thank you in advance!

Yajuan
Hello! I have the same problem, too. I don't know that if you had solved the problem, could you give me same advice about the error? My model is also coupled structual and thermal multiphysics with friction, when I use stationary slover ,the nonlinear solver has no convergence. So i tried the time-dependent solver algorithm, it occurs error 7220. In the HELP file, it says: the solve contact problems,use the augmented Lagrangian method. I think the augmented Lagrangian method is Stationary solver, what I should do with the time-dependent solver? Thank you in advance! Yajuan

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Posted: 9 years ago 23.03.2011, 00:02 GMT-4
Hello!

I had the problem,too.

Does "Comsol can't solve contact problems time-dependent! " mean that there is no time-dependent solver for contact problem , if we try to solve the problem ,we should use the script?

About "You have to change certain settings in the model in order to use time-dependent solving." Could you please give me more details about "change certain setting"?

Thank you in advance!

Yajuan

Hello! I had the problem,too. Does "Comsol can't solve contact problems time-dependent! " mean that there is no time-dependent solver for contact problem , if we try to solve the problem ,we should use the script? About "You have to change certain settings in the model in order to use time-dependent solving." Could you please give me more details about "change certain setting"? Thank you in advance! Yajuan

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Posted: 9 years ago 09.04.2011, 09:12 GMT-4
Hi everybody,

I have the same problem to, please, if someone could send a model or explain clearly the steps to make the contact problem work in time-dependent I'd be very grateful.

Thanks.
Hi everybody, I have the same problem to, please, if someone could send a model or explain clearly the steps to make the contact problem work in time-dependent I'd be very grateful. Thanks.

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Posted: 9 years ago 09.04.2011, 12:00 GMT-4
Hi

why do you need the time dependence ? to see the bouncing around of the contact ?

or is it just that you want a load that is increasing with time ?

If so use a stationary with a parameter called "t" and it's done

my model is a 4.1 (sorry I have left 3.5 behind ;)
--
Good luck
Ivar
Hi why do you need the time dependence ? to see the bouncing around of the contact ? or is it just that you want a load that is increasing with time ? If so use a stationary with a parameter called "t" and it's done my model is a 4.1 (sorry I have left 3.5 behind ;) -- Good luck Ivar

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