Mutual dependance iteration [SOLVED]

[teepeeaye]

Hi.

I am trying to get Elmer to calculate an electric resistance in a model where temperature is a depending variable.

Sounds simple but I am not quite sure it is, as both thermal conductivity and electrical conductivity depend on temperature and the (steady state) temperature distribution depends on on both thermal conduction as well as local heat source.

In my material definitions I have declared

Heat Conductivity = Variable Temperature
MATC "a function in tx"
Electric Conductivity = Variable Temperature
MATC "another function in tx"

Is that all there is to do or is there some special way I need to tell Elmer that it should iterate both equations (current (with ohmic heat) AND thermal conduction) simultaneously. From the log file it seems that Elmer first iterates one equation and then iterates the other equation, and thats it.

In solver settings both main equations are set to run "Always" and I also have a fluxsolver which is set to run "Before saving".

Thanks for reading and for helpful responses.

PS: I should mention that I have a BodyForce with the "joule heat" checked for the Heat Conduction equation.

[Rich_B]

Hello,

There is a webinar presentation that talks about this topic, it may be useful for you:

https://www.nic.funet.fi/pub/sci/physics/elmer/webinar/

and look for this doc:

12-ElmerWebinar-CoupledProblems-PeterRaback.pdf

Rich.

[teepeeaye]

Thank you very much Rich_B and Peter Råbak

Just what I needed. In the GUI "Steady State Max Iterations" is defined in the menu: Model->Setup and the "Steady State Convergence Tolerance" is defined per solver in the Equation settings.