CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

Turbulent Viscosity Modification

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 31, 2007, 07:38
Default Turbulent Viscosity Modification
  #1
Magnoli
Guest
 
Posts: n/a
Hi!

I'm using CFX-10 and I need to use a particular definition for the turbulent (eddy) viscosity. Since this is no input variable, can I do it using a CEL routine or do I have to use the MMS in a user routine? If MMS is needed, could anyone tell me the path of turbulent viscosity in it?

Thanks.
  Reply With Quote

Old   October 31, 2007, 07:46
Default Re: Turbulent Viscosity Modification
  #2
opaque
Guest
 
Posts: n/a
Dear Magnoli,

You should be able to overwrite the Eddy Viscosity under the Advanced Control of the turbulence model using a CEL expression.

Hopefully, you should not need any userCEL routine to do this. As an additional advice, overwriting data directly on the MMS is not a good practice that can lead to strange/bizarre behavior. The ANSYS CFX solver has specific API's to write/update data that when circumvented could produce undesirable results.

Hope this helps,

Juan Carlos

  Reply With Quote

Old   October 31, 2007, 08:11
Default Re: Turbulent Viscosity Modification
  #3
Magnoli
Guest
 
Posts: n/a
Dear Juan Carlos,

this is exactly what I needed!

Thanks a lot, Marcelo.
  Reply With Quote

Old   September 16, 2015, 10:56
Default
  #4
New Member
 
Join Date: Mar 2015
Posts: 3
Rep Power: 11
sobou is on a distinguished road
Dear all,
I am using CFX-16.0, and I want to modify the eddy viscosity just like Magnoli. However, since I try to simulate a multiphase flow, I just do not get what does CFX when modifying the eddy viscosity with the user-interface "Advanced Turbulence Control". It is a homogeneous multiphase case, so I have 2 eddy viscosity and I do not understand why they are different? Does the solver not only solving k-epsilon turbulence equations for 1 "mixture" fluid? What is the link between these 2 eddy viscosities? Which one is affected by the modification allowed through the Advanced Turbulence Control?
Sobou
sobou is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
reversed flow at pressure inlet and turbulent viscosity is limited.... cfdiscool FLUENT 10 June 10, 2015 07:15
k-epsilon problem: non-physical turbulent viscosity production in coaxial free-jet Felipeb Main CFD Forum 1 July 26, 2010 18:02
Turbulent viscosity and shear rate shib FLUENT 0 June 22, 2010 13:44
setting value of turbulent intensity and turbulent viscosity ratio in wind tunnel nuimlabib Main CFD Forum 0 August 4, 2009 01:05
Problem of Turbulent Viscosity Ratio Limited David Yang FLUENT 3 June 3, 2002 07:13


All times are GMT -4. The time now is 20:56.