CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM Programming & Development (https://www.cfd-online.com/Forums/openfoam-programming-development/)

 David_010 December 5, 2011 18:16

Hi to all,

I have been working with the solver porousSimpleFoam (incompressible flow: liquid metals) with isothermal cases and know I need to move to a heat transfer problem, also with porous media. For that, I need to add the temperature equation to the solver. I know how to do with the common temperature equation, but not how to do for the porous media. So, any idea of how to do that?

David

 Ola Widlund December 6, 2011 07:52

Hi David,

I think you should bring out pen and paper and think about the mathematical description of your system. You can let your computer rest until you've finished...

Do you have different temperatures in fluid and solid? How do you represent thermal inertia of the solid (probably two different temperature fields)? How do you intend to model the heat transfer between fluid and solid (the porous media)? Do you have an empirical relation for that? Over what surface area does the heat transfer take place? And what's the shape of the interface? What assumptions can you make about turbulence in the porous medium?

Once you have a clear picture of the above, I think you will also have some ideas about what's needed for the numerical modeling. That's the easy part. :)

/Ola

 Ola Widlund December 6, 2011 07:53

Oh, I forgot: What about phase change?!

/Ola

 David_010 December 6, 2011 08:50

Hi Ola,

Firs of all, thank you very much for your answer. My idea is to simulate a nuclear reactor core. The fuel bundles will be aproximated as porous media. As a first approximation (and I now that is not real at all) I want to suppose uniform temperature between bundles and fluid (liquid metal), so, only one equation is needed, and no phase change. I need also to add an internal heat generation therm.

For a more advanced version, I will add heat transfer between solid and liquid and two temperature equations (liquid and solid), but first I want to start with a simple version.

Asuming that, how to relate the values present on the temperature equation (porosity...) with the porousSimpleFoam solver?

Thankyou very much again,

David

 romant June 21, 2012 05:47

Have you ever been successful with your temperature equation input?

Quote:
 Originally Posted by David_010 (Post 334853) Hi Ola, Firs of all, thank you very much for your answer. My idea is to simulate a nuclear reactor core. The fuel bundles will be aproximated as porous media. As a first approximation (and I now that is not real at all) I want to suppose uniform temperature between bundles and fluid (liquid metal), so, only one equation is needed, and no phase change. I need also to add an internal heat generation therm. For a more advanced version, I will add heat transfer between solid and liquid and two temperature equations (liquid and solid), but first I want to start with a simple version. Asuming that, how to relate the values present on the temperature equation (porosity...) with the porousSimpleFoam solver? Thankyou very much again, David

 David_010 June 21, 2012 07:35

Hi Roman,

Yes, I was succesful. In my case I asumed equilibrium between solid and liquid so averaged properties are used (thermal conductivity, viscosity). I also added the buoyancy term and internal heat generation. Results were in good agreement with available numerical and experimental results in the literature regarding a square cavity with porous and fluid layers.

David

 romant June 21, 2012 07:47

Quote:
 Originally Posted by David_010 (Post 367627) Hi Roman, Yes, I was succesful. In my case I asumed equilibrium between solid and liquid so averaged properties are used (thermal conductivity, viscosity). I also added the buoyancy term and internal heat generation. Results were in good agreement with available numerical and experimental results in the literature regarding a square cavity with porous and fluid layers. David
Have you published the results somewhere? And is it possible to obtain the source code?

 papteo February 18, 2013 09:42

Quote:
 Originally Posted by romant (Post 367632) Have you published the results somewhere? And is it possible to obtain the source code?
Hi ,

I am interesting also for the implementation of the energy equation in porous media. Is it possibly to give us some more information about the programming? I would be really grateful if you could send me some more information (e.g. code).