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[waves2Foam] Turbulence problems, possibly due to density issues

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Old   December 5, 2015, 08:34
Default Turbulence problems, possibly due to density issues
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Hi ngj,
Thanks for the powerful tool.
I got the desired result when I generated wave using laminar.But when i switch to turbulence model,say RNG k-epsilon,the surface elevation at a certain probe decays significantly.I think the problem maybe the missing of density term in the k&epsilon equations afterI read your phd thesis (N. G. Jacobsen 2011. ) and the post below:
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Originally Posted by ngj View Post
Hi Nima,

Well the short answer is yes that turbulence models have been coupled with waveFoam, however, if you strictly stick to the turbulence formulations in OpenFoam, you will get poor results, as the turbulence formulation in OF does not consider the density in the equations, hence excessive diffusion of turbulence takes place over the interface, which results in rapid decay in the wave height.

Therefore, you need to formulate the turbulence equations correctly, namely including density in the turbulence equations.

Best regards,

Niels


So is there any guide to modify the turbulence equations as I am not familia with the C++..
Thank you in advance
Aloha

Last edited by wyldckat; August 25, 2018 at 12:18. Reason: changed post number to quoted post
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Old   December 6, 2015, 15:20
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Niels Gjoel Jacobsen
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Good evening,

@Aloha: No, there is no guide available that described how to include the density in the turbulence closure. Please verify that the scale of your problem actually requires a turbulence model.

Kind regards,

Niels
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Last edited by wyldckat; August 25, 2018 at 12:18. Reason: removed answers to other posts that were on the main thread
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