Choosing turbulence parameters

saisanthoshm88 · April 13, 2013, 16:37

Which approach is better for the turbulence conditions - eddy viscosity ratio, intensity If we don't know what values to use.

Either inputting some values that suit the physics (or) Using expressions
to gather them as the solution progresses for instance - volumeAve(eddyviscosityratio)@DomainName

ghorrocks · April 14, 2013, 08:17

This question seems to miss the point a bit. For the common 2 eqn turbulence models you have two terms to define - a turbulence energy component (ie have intense the turbulence is) and "something else", where the something else could be a length/time scale, dissipation rate or something else.

So you need to define these two parameters for turbulence. Then just define them in the way which matches what you are trying to model best.

April 13, 2013, 16:37	Choosing turbulence parameters	#1
saisanthoshm88 Senior Member --------- Join Date: Oct 2010 Posts: 303 Rep Power: 18	Which approach is better for the turbulence conditions - eddy viscosity ratio, intensity If we don't know what values to use. Either inputting some values that suit the physics (or) Using expressions to gather them as the solution progresses for instance - volumeAve(eddyviscosityratio)@DomainName __________________ Best regards, Santhosh.

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April 14, 2013, 08:17		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,852 Rep Power: 144	This question seems to miss the point a bit. For the common 2 eqn turbulence models you have two terms to define - a turbulence energy component (ie have intense the turbulence is) and "something else", where the something else could be a length/time scale, dissipation rate or something else. So you need to define these two parameters for turbulence. Then just define them in the way which matches what you are trying to model best.