CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CD

Iteration

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

Like Tree1Likes
  • 1 Post By abdul099

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 4, 2012, 02:51
Post Iteration
  #1
New Member
 
Join Date: Dec 2011
Posts: 2
Rep Power: 0
btlau is on a distinguished road
How long does 1 Iteration (Iter) represent in Star-CD? 1 minute?
My CFD model returns different heat pattern at ITER=1000 and ITER=1500.
Thanks.
btlau is offline   Reply With Quote

Old   April 5, 2012, 02:19
Default
  #2
Member
 
zheng jianjun
Join Date: Jan 2010
Posts: 46
Rep Power: 16
skylent is on a distinguished road
transient or steady case? timestep==??
skylent is offline   Reply With Quote

Old   April 30, 2012, 18:26
Default
  #3
Senior Member
 
Join Date: Oct 2009
Location: Germany
Posts: 636
Rep Power: 21
abdul099 is on a distinguished road
You didn't really understand what steady state means, did you? Did you ever in your live hear a CFD lecture?
An iteration does NOT represent any time. When running a steady state case, the converged solution will represent the state after an infinite long time. Even worse, every cell might be on a different (virtual) time level, so a steady state solution just makes sense when it's fully converged. It is NOT possible to pick the solution at some different iteration counts and compare them except for fools.
When your solution changes when the iteration advances (assuming you're running steady state), it is not yet converged. Keep on iterating until the solution does not change anymore. When it takes long, it takes long. But you need to run until the solution does not significantly change, everything else is just bullshit!
Blanco likes this.
__________________
We do three types of jobs here:
GOOD, FAST AND CHEAP
You may choose any two!
abdul099 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
[snappyHexMesh] No layers in a small gap bobburnquist OpenFOAM Meshing & Mesh Conversion 6 August 26, 2015 09:38
how to increase "Newton Pressure Iteration Limit" kus CFX 9 April 21, 2013 01:54
[snappyHexMesh] snappyHexMesh aborting Tobi OpenFOAM Meshing & Mesh Conversion 0 November 10, 2010 03:23
Parallel runs slower with MTU=9000 than MTU=1500 Javier Larrondo FLUENT 0 October 28, 2007 22:30
Heat exchanger problem chiseung FLUENT 16 October 20, 2001 04:36


All times are GMT -4. The time now is 20:51.