CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > FLUENT

help! cyclone convergence question

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

LinkBack Thread Tools Search this Thread Display Modes
Old   January 19, 2005, 22:04
Default help! cyclone convergence question
Posts: n/a
I am doing simulation about cyclone separator by FLUENT, When I use RNGk-e turbulent model, convergence is easy to achieved, when I switched to RSM turbulent model, first residuals drop, velocity distribution looks like very good, then residuals rise abruptly and keep a horizontal level, velocity distribution deteriorates. All solving adopted PRESTO, QUICK scheme, and steady solver, and when using RSM, drop under-relaxtion facters a bit. How to keep RSM final convergence?

Thank you very much.

  Reply With Quote

Old   January 26, 2005, 16:29
Default Re: help! cyclone convergence question
Posts: n/a
Often times, with cyclones, the RSM captures the precessing vortex core which is an unsteady phenomena. When the RSM is used with the steady solver, the solutions would not converge, typically showing a limit-cycle like behavior. Try the same problem with the unsteady solver. Chance is that you'll see the RSM captures the precession of the vortex core.
  Reply With Quote


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
Fluent: Tet Vs Poly mesh novice FLUENT 9 January 3, 2011 13:10
Convergence question with regards to discretization karananand Main CFD Forum 0 July 16, 2010 01:27
Question about convergence criteria? Thomas FLUENT 7 April 8, 2005 20:38
Discretisation / Convergence Question Johnny B FLUENT 1 November 15, 2003 15:27
Convergence Question Colin FLUENT 13 May 16, 2003 12:41

All times are GMT -4. The time now is 08:00.