CFD Online Logo CFD Online URL
Home > Forums > CFX

eddy viscosity

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   April 3, 2006, 16:03
Default eddy viscosity
Posts: n/a
Hi all,

I have one more question. The cfx manual states that eddy viscosity should be of the order of 1000 times the dynamic viscosity for a fully turbulent flow. I am checking the values of eddy viscosity in the domain and it varies 0-300 times to dynamic viscosity. How does this affect the results? So if most part of the domain is not fully turbulent what happens? any help would be very much appreciated.

  Reply With Quote

Old   April 4, 2006, 13:12
Default Re: eddy viscosity
Posts: n/a
Hi Mike,

It's hard to say exactly what the effect will be. Most Turbulence models are created by making some simplifying assumptions about the Reynolds averaged flow. These assumptions may no longer apply.

See how your results compare when you run laminar flow. You could also try the SST transition model, although I suggest reviewing the documentation carefully to ensure its applicability as well.

Regards, Robin
  Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Boussinesq eddy viscosity assumption siw Main CFD Forum 2 February 17, 2011 13:30
Eddy Viscosity Transport Model Jade M Main CFD Forum 0 April 21, 2010 14:17
Link between eddy viscosity and subgrid-scale turbulent viscosity in LES Marvin Main CFD Forum 6 December 4, 2009 12:08
Question about eddy viscosity ratio limit Piti CFX 2 January 17, 2008 17:49
Vertical eddy viscosity in channal flow? Liu Main CFD Forum 0 June 15, 2004 21:07

All times are GMT -4. The time now is 08:16.