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

CFD++ Residual plot and convergence problem

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 30, 2014, 07:17
Question CFD++ Residual plot and convergence problem
  #1
New Member
 
Emre
Join Date: Jul 2014
Posts: 1
Rep Power: 0
Emre is on a distinguished road
Hello,
I am new in the website, and would really appreciate all of your help.

I have a basic 2D mesh and I am trying to do a grid convergence study. It is a study of hypersonic flow with a lot of reactions and plasma flow (re-entry). I used ICEM to generate the mesh and then used CFD++. Although my first mesh(which was coarser) converged and the residuals dropped until nearly e-4, when I decreased the cell sizes a little bit and made some little corrections on the parameters of exponential1 on an edge in ICEM, I obtained a residual plot which dropped only until between e-1 and e-2 (residual plot is also attached).
I ran the program until 5000 steps but there was no use.

What can be the reason?
Should a residual plot drop until e-10 orders?
Can I use my results, are they correct with a residual like that?
What really does the residual plot mean?

Thanks in advance
Emre
Attached Images
File Type: png Screenshot.png (10.7 KB, 10 views)
Emre is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
PyFoam braennstroem OpenFOAM 294 January 27, 2016 08:33
Problem with Residual plot raising up to hige numbers na do not converge fardinkhalili STAR-CCM+ 4 March 25, 2014 10:35
Unable to get converged solution using SimpleFoam jr33 OpenFOAM Running, Solving & CFD 5 February 16, 2013 05:43
Max Residual Post Plot Ed CFX 5 March 13, 2009 09:41
AMG parallelisation and convection schemes christian OpenFOAM Running, Solving & CFD 3 December 17, 2007 09:21


All times are GMT -4. The time now is 07:12.