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Gearb0x May 19, 2010 05:14

Values of epsilon
 
Dear Foamers,

I'm currently running a simulation with theses settings :

- Launder Sharma KE for turbulence model
- RANS
- SimpleFoam solver

what I would like to know is typical values of epsilon near the walls?
I know I have to impose a BC epsilon <<<< 1 at the wall for Low-Re model.

Right now I'm running a simulation and I'm getting values of epsilon of 6000 - 8000 near the walls. Is it possible? Where could I find information about this?

Thanks for your help

maddalena May 20, 2010 03:16

Quote:

Originally Posted by Gearb0x (Post 259426)
Dear Foamers,

I'm currently running a simulation with theses settings :

- Launder Sharma KE for turbulence model
- RANS
- SimpleFoam solver

what I would like to know is typical values of epsilon near the walls?
I know I have to impose a BC epsilon <<<< 1 at the wall for Low-Re model.

Hallo Gearb0x,
what I usually do whit the same turbulence model and solver as you is to use a zeroGradient BC for both k and epsilon at the wall...
Hope this help, cheers,

mad

Gearb0x May 20, 2010 12:36

Hi,

About boundary conditions, I'm sure @99% that setting k and epsilon @0 @walls is the way to do it. Well, actually not zero but a very low value as 1e-06 for example..

I've seen someone skilled in turbulence to check my simulation and he thinks that my results are good. I get epsilon values of about 5000 - 10 000 near the walls and to him, this is logical.

Regards


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