[Antoniorp]

Hello everyone,

I have some questions regarding turbulent models with openfoam.

Using first order models like k-epsilon or k-omega SST is it possible to easily obtain second order quantites, like u'v' ? If yes, how is that done? Or the only way to obtain those quantities is through another turbulence model?

Thanks,

António

[icaroaccordi]

No, it is not. They use isotropic turbulence assumption. You need a Reynolds stress model (second closure) to do that. LRR is a example that is already implemented in OpenFoam.

[Antoniorp]

Thank you for your reply!

Antonio

[taxalian]

Originally Posted by Antoniorp

Hello everyone,

I have some questions regarding turbulent models with openfoam.

Using first order models like k-epsilon or k-omega SST is it possible to easily obtain second order quantites, like u'v' ? If yes, how is that done? Or the only way to obtain those quantities is through another turbulence model?

Thanks,

António

Hi António,

I would say if you don't prefer to use Reynolds Stress Model that can directly get the shear stresses i.e. u'v', so for the turbulence modles like k-epsilon or k-omega SST you can use the simple Boussinesq relation (http://www.cfd-online.com/Wiki/Bouss...ity_assumption) to obtain the quantities like u'v'.

Regards,
Taxalian