turbulent length scale
 

Hi all,

its a very simple question!

Is the turbulence length-scale in OpenFOAM based on the mixing-length ?

Its due to the fact of estimation of l

l = d_hyd * 0.038
l = d_hyd * 0.07


I am not 100% sure what to use.
In the past I thought that OF uses only the length-scale so I used always 0.038


Thanks in advance.
Tobi

i dont know for what you need it excatly but for this BC

turbulentMixingLengthDissipationRateInlet

you need the mixinglength 0.07.

Hi,

thanks for your reply.

I just wanted to know how to calculate the length scale for the cfd-online calculator:

http://www.cfd-online.com/Tools/turbulence.php


But thanks for your replay. So I think I need to set up the mixingLength (0.07) for the omega BC too.

Looking for Reference
 

Can you please provide me a reference from where you got the equations:
l = d_hyd * 0.038
l = d_hyd * 0.07

Thanks in advance.

Hi,

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

Thanks Tobi,
I had already seen that.
I am looking for a literature (text book / journal paper) reference and not a web-page reference.

Hi, Foamers!

Can I get your valuable suggestions?
I would like to track the Turbulent length scales at every time step and at a particular location in flow field, 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., ?

My main intention of doing this is, I wanted to compare my simulation jet (modeled by RANS) turbulent length scales with experimentally measured length scales.

Thanks,
UHGAR