Turbulent Length Scale
 

I'm running a case with simpleFoam, stationary flow

I'd like to know how to estimate the Turbulent Length Scale, which by default is set to 0.125 (I use Discretizer to setup OpenFoam cases)

I understand this parameter has relation with the Viscous Wall Layer, and may be deduced from the expression NU/U*, being U* the Friction Velocity which is defined as sqrt(shear_stress/rho)

The question is how to estimate near wall shear stress in order to calculate the Turbulent Lenght Scale, or if there is an easier rule to obtain this parameter.

Thanks for the comments,

turbulent length scale
 

Hi,

Please have a look here

http://www.cfd-online.com/Wiki/Turbulence_length_scale

Regards,
Dhruv.

thank's a lot, Dhruv

Hi, Foamers!

Can I get your valuable suggestions?
I would like to track the Turbulent length scales at every time step and use it in paraFoam as well in quantitative post processing. How can I do it?

How the length scales field will be created just like u,p, k etc., ?

Thanks,
UHGAR