Synchronizing target variables and fields of EOF-Library

Numerical methods and mathematical models of Elmer
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annier
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Synchronizing target variables and fields of EOF-Library

Post by annier »

Hi All,
I want to export "joule heating" from Elmer to OpenFOAM via EOF-Library. As discussed in the Elmer tutorial, for joule heating https://github.com/ElmerCSC/elmerfem/bl ... M/case.sif, I would like to employ joule heating (qjoule) as the source term in TEqn.H file (https://github.com/anilkunwar/OpenFOAM_ ... oam/TEqn.H). So my basic query is:
1. What is the unit of joule heating as target variable in Elmer? h_q is in W/kg and S_qjoule = \rho* h is in W/m^3.
2. As I have written it as

Code: Select all

...
 fvScalarMatrix TEqn
    (
        fvm::ddt(T)
      + fvm::div(phi, T)
      - fvm::laplacian(alphaEff, T)
     == qjoule*alphaEff/kappa
); 
...
,
I suppose the unit of qjoule of openfoam and "joule heating" from Elmer have the same dimensions if the right hand side (RHS) of equation is written as in the code. In RHS of the equation, kappa is thermal conductivity (W/m K), alphaEff is thermal diffusivity (m^2/S) and qjoule is joule heating (W/m^3).

Can anyone verify whether this is correct or not?

Note: it is assumed that the temperature dependence of sigma (electrical conductivity) is addressed during Elmer simulation and thus qjoule is solved as source term not dependent on T variable.

References:
1. https://github.com/ElmerCSC/elmerfem/tr ... ToOpenFOAM
2. https://eof-library.com/

Yours Sincerely,
Anil Kunwar
Anil Kunwar
Faculty of Mechanical Engineering, Silesian University of Technology, Gliwice
vencels
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Re: Synchronizing target variables and fields of EOF-Library

Post by vencels »

Hi Anil,

1) Yes, Joule heating in Elmer is in W/m3.
2) Not sure whether you need to use alphaEff or nu()/Pr. Thinking about kappa (thermal conductivity) I think it is typically measured for non-moving fluids and gasses. To be on safe side, better ask someone with CFD knowledge :)
annier
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Joined: 27 Aug 2013, 13:51
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Re: Synchronizing target variables and fields of EOF-Library

Post by annier »

Hi Juris,
1. Thanks for conforming the unit of "joule heating = \rho *h" in Elmer.
2.My present goal is to couple static current solver of Elmer with heat and fluid flow solvers (applications) of openFoam. But since the accuracy of this constant field is important for CFD , I will look more deep into the usage of alphaEff or Nu()/Pr. I am so motivated to utilize EOF-Library for coupled heat transfer and joule heating simulation. EOF-Library has added a new dimension of advanced fluid mechanics utilization in addition to the strengths of Elmer. Keep it up with your innovative inputs.

Yours Sincerely,
Anil Kunwar
Anil Kunwar
Faculty of Mechanical Engineering, Silesian University of Technology, Gliwice
annier
Posts: 1168
Joined: 27 Aug 2013, 13:51
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Re: Synchronizing target variables and fields of EOF-Library

Post by annier »

Updates on OpenFoam to Elmer Solver:
Please find the code commitments on github by Peter.
https://github.com/ElmerCSC/elmerfem/co ... 3fa410ba6b
https://github.com/ElmerCSC/elmerfem/tr ... omOpenFOAM


Yours Sincerely,
Anil Kunwar
Anil Kunwar
Faculty of Mechanical Engineering, Silesian University of Technology, Gliwice
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