Turbulence

darookie · October 23, 2009, 12:15

Do you know any equation to determine the turbulence intensity, because I need initial values for the k epsilon model.
With the following equations i could calculate them regarding to the mixing model:

$k= 2/3*(U_{ref} T_i)^2$
$\epsilon=C_\mu^{3/4} *\frac{k^{3/2}}{l}$

Is this approach common or are there other proceedings?
Thanks for your replies

ghorrocks · October 24, 2009, 06:54

Have a look in a turbulence modelling textbook. "Turbulence Modelling for CFD" by Wilcox is the one I use. That will explain the origins for a whole bunch of models.

Alternately have a look at either what you know about the turbulence field fro mthe experimental results OR have a look at the turbulence definitions available in CFX to see the other options.

October 23, 2009, 12:15	Turbulence	#1
darookie New Member Andrej Hoyningen Join Date: Jul 2009 Posts: 22 Rep Power: 17	Do you know any equation to determine the turbulence intensity, because I need initial values for the k epsilon model. With the following equations i could calculate them regarding to the mixing model: $k= 2/3(U_{ref} T_i)^2$ $\epsilon=C_\mu^{3/4} \frac{k^{3/2}}{l}$ Is this approach common or are there other proceedings? Thanks for your replies

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October 24, 2009, 06:54		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	Have a look in a turbulence modelling textbook. "Turbulence Modelling for CFD" by Wilcox is the one I use. That will explain the origins for a whole bunch of models. Alternately have a look at either what you know about the turbulence field fro mthe experimental results OR have a look at the turbulence definitions available in CFX to see the other options.