CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

non-linear k-epsilon model implementation problems

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 20, 1998, 05:25
Default non-linear k-epsilon model implementation problems
  #1
Saidi
Guest
 
Posts: n/a
I am currently working on implementaion of a non-linear k-eps model in an in-house code (a FVM code) which was originally written for linear EVM models. I can calculate Reynolds stresses pretty well with the explicit ASM model when I am still using linear EVM. It was just a check for me to see if there was any problem with Reynolds stress calculation. It showed that there is not. But when I try to put gradients of those calculated Reynolds stresses as source terms in the momentum equations and skip eddy viscousity concept, I got ckeker-board problem and instability. I have been familiar with the problem and so I tried Obi-Peric-Scheuerer's method (AIAA J., Vol. 29, No.4, 1991, pp. 585-590), but I have still the same problem. If there is anyone out there who actually done this kind of coding work, I will be most grateful if he/she shares some of his/her experiences with me.
  Reply With Quote

Old   August 12, 1998, 10:39
Default Re: non-linear k-epsilon model implementation problems
  #2
Anders Joenson
Guest
 
Posts: n/a
Hello! I have done some coding of non-linear k-epsilon models into the commercial CFD code CFX4. I implemented it into the standard k-eps treatment of CFX, separating the stress-strain relation into two parts. The first part is the standard linear term (already implemented in the code), the second part is the HOT (higher order terms, which can be quadratic or cubic or whatever). After calculating the HOT in the momentum equations, the appropriate gradients of these are added as source terms. This worked fine for me.

Anders
  Reply With Quote

Old   March 4, 2010, 13:23
Default
  #3
Senior Member
 
Claus Meister
Join Date: Aug 2009
Location: Wiesbaden, Germany
Posts: 241
Rep Power: 18
idrama is on a distinguished road
Hello Saidi!

Do you have any reference for the non-linear k-epsilon modell?

Cheers,

Claus
idrama 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
[ICEM] Problems with coedge curves and surfaces tommymoose ANSYS Meshing & Geometry 6 December 1, 2020 11:12
OpenFoam implementation of Wilcox's latest k-omega model swetkyz OpenFOAM 3 June 19, 2017 11:05
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 18 March 3, 2015 05:36
solution diverges when linear upwind interpolation scheme is used subash OpenFOAM 0 May 29, 2010 01:23
Problems with own LES Model Implementation fs82 OpenFOAM 1 October 9, 2009 10:31


All times are GMT -4. The time now is 02:17.