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

Convergance !!!!!!!!!!!

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 3, 2006, 22:51
Default Convergance !!!!!!!!!!!
  #1
Neser
Guest
 
Posts: n/a
in spray particles tracking process, I got the following CFX solver results

1- U-Mom RMS Res 4.8E-03

U-Mom Max Res 8.8E-02

V-Mom RMS Res 4.7E-03

V-Mom Max Res 8.8E-02

W-Mom RMS Res 2.1E-02

W-Mom Max Res 5.8E-01

P-Mass RMS Res 6.5E-05

P-Mass Max Res 4.7E-03

U-Mom Domain Imbalance, in %: 0.0110 % V-Mom Domain Imbalance, in %: -0.0010 % W-Mom Domain Imbalance, in %: 1.7424 % P-Mass Domain Imbalance, in %: -0.0283 %

Is the could be convergant results

regards

  Reply With Quote

Old   June 4, 2006, 22:32
Default Re: Convergance !!!!!!!!!!!
  #2
Michael
Guest
 
Posts: n/a
fairly high W-mom imbalance. plus those RMS values are high IMO. I wouldn't trust the solution how was the residual trace? oscillating can be a function of the grid resolution and also the model selected. what models are you using? how is your grid in the are of the max residuals? is it a coarse grid (grid topology would be nice) in this area and is there a large velocity gradient or recirculation in this area?

in our work, if we are having problems converging we require two orders or magnitude difference between the RMS and MAX residuals, then we look where those max residuals are located.
  Reply With Quote

Old   June 6, 2006, 09:36
Default Re: Convergance !!!!!!!!!!!
  #3
Neser25
Guest
 
Posts: n/a
Thank you for your reply, about your questions:

1. I am using particle tracking model. Therefore, as far as I know, mesh size has not a great effect.

2. particle injection downward speed is about 8 m/s, however, the upword hot air spped is 0.1 m/s)

3. I do not know how I can get the place which has max residuals.

Regards

  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
Free Surface Problem - Convergance Toby FLUENT 0 July 3, 2008 00:16
CONVERGANCE IN IMMERSOL RADIATION MODEL anjani Phoenics 9 February 21, 2006 09:45
ADI-SOR convergance Mohsen Main CFD Forum 2 November 14, 2005 21:43
Second order convergance. Rob FLUENT 2 July 20, 2004 11:49
mass convergance subhash Siemens 2 September 9, 2002 02:14


All times are GMT -4. The time now is 20:33.