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

Realizable K-epsilon settings

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 6, 2003, 09:09
Default Realizable K-epsilon settings
  #1
Stephen Mar
Guest
 
Posts: n/a
I am currently preforming a CFD validation on a 6:1 Spheroid with incompressible viscous flow. I am attempting to illustrate vortex sheading using the realizable k-epsilon model. However I have found that the standard setting and those settings suggested by my colleagues do not provide a stable solution. Fluent returns the following error message "turblent viscousity limited to 1e5 in X-number of cells". My question is, what settings have worked sucessfully in the past for this type of flow, and what type of near wall modelling have bee used? Currently enhanced wall treatment, with pressure gradient effects are being used. With thanks Stephen Mar

  Reply With Quote

Old   March 6, 2003, 16:41
Default Re: Realizable K-epsilon settings
  #2
heydari
Guest
 
Posts: n/a
I have used all the models of k-e, with the default values, and different wall functions, and the final results were so acceptable, even more than what was supposed.
  Reply With Quote

Old   March 10, 2003, 05:18
Default Re: Realizable K-epsilon settings
  #3
Volker Pawlik
Guest
 
Posts: n/a
The default limit of turbulent vicosity ratio may be exceeded in cases of strong turbulence.

Hence it is not a fixed limit which must be kept by all means.

  Reply With Quote

Old   March 10, 2003, 07:37
Default Re: Realizable K-epsilon settings
  #4
Christian
Guest
 
Posts: n/a
Why do you think that it is the settings that is the problem ?

As Volker says, it is not given that the ratio should be below 1e5.

A poor solution can be obtained due to many operator-errors and not just because of ill-chosen model constants.
  Reply With Quote

Reply


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
SimpleFoam k and epsilon bounded nedved OpenFOAM Running, Solving & CFD 16 March 4, 2017 08:30
Orifice Plate with a fully developed flow - Problems with convergence jonmec OpenFOAM Running, Solving & CFD 3 July 28, 2011 05:24
BC settings to expand pressure on atmosphere - simpleFoam / totalPressure sErik OpenFOAM Running, Solving & CFD 1 June 15, 2011 02:49
How to get reference to k and epsilon in the epsEqn and kEqn cfd_explorer OpenFOAM 0 March 10, 2011 09:58
SimpleFoam k and epsilon bounded nedved OpenFOAM Running, Solving & CFD 1 November 25, 2008 20:21


All times are GMT -4. The time now is 17:04.