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

solution convergence and mesh density in k-omega model (FLUENT)

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 29, 2015, 17:09
Default solution convergence and mesh density in k-omega model (FLUENT)
  #1
New Member
 
ripong
Join Date: Oct 2011
Posts: 6
Rep Power: 10
ripong is on a distinguished road
I am running k-omega model with low Reynolds number correction using FLUENT. My 3-D geometry looks like a tree with multiple inlets with a single outlet. The Reynolds number at the outlet tube (it is maximum there) is ~13000 and at inlet tubes are ~500.

After running it for thousands of iterations, residuals for mass convergence and xyz velocities reached close to 1e-6 and started fluctuating in that range. But residuals for k and omega values do not decrease less than 1e-5.

My questions are
1. Is it alright to apply more stringent convergence rules for mass and xyz velocities and more lenient for the k and omega values?
2. What are the residual values "generally accepted" for solution convergence for each quantities?
3. I decreased the mesh density and the solution converged better (i.e., residuals reached lower level). Is this alright to trust the coarse mesh solution than the finer one? Both look similar except for small structures appear in the highest velocity domain in the finer mesh solution. I wonder if this is real or an artifact. How should I verify?

Thank you!!
ripong is offline   Reply With Quote

Reply

Tags
convergence problem, k-omega model, mesh density

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
Convergence Centurion2011 FLUENT 47 February 12, 2020 11:18
sliding mesh problem in CFX Saima CFX 45 September 22, 2015 10:53
Overflow Error in Multiphase Modelling with Two Continuous Fluids ashtonJ CFX 6 August 11, 2014 14:32
Naca 0012 (compressible and inviscid) flow convergence problem bipulsaha FLUENT 1 July 6, 2011 07:51
increasing mesh quality is leading to poor convergence tippo CFX 2 May 5, 2009 10:55


All times are GMT -4. The time now is 11:52.