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

Update boundary condition only after several iteration

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 13, 2009, 10:35
Default Update boundary condition only after several iteration
  #1
New Member
 
Valerio Novaresio
Join Date: Mar 2009
Location: Polonghera, Cuneo, Italy
Posts: 27
Rep Power: 8
novyno is on a distinguished road
Hi

I have to implement a boundary condition of type fixedGradient. The gradient depends from the field value. To implement the boundary condition I have modified the updateCoeff() funcion. Unfortunately in this way the gradient changes in every iteration (becouse in every iteration the updateCoeff() function is called) and the solution became instable.

Is there some way to update the boundary condition value only after several iterations and not every iteration?

Thanks...
__________________
...The best way to acquire new knowledge is to share it...
novyno is offline   Reply With Quote

Old   July 16, 2009, 11:04
Default
  #2
Member
 
Julien Schaguene
Join Date: Apr 2009
Location: France
Posts: 55
Rep Power: 8
Schag is on a distinguished road
Hi,

I never tried it but the first solution that comes to my mind is to use a counter.
For example, if you want to change every 10 iterations, just make count=count+1 for each one, and when count=10 do (updateCoeffs() & count=0)

Sorry if it seems stupid and I'm far away from the point, I'm a beginner trying to contribute as I can.

Regards

Julien
Schag is offline   Reply With Quote

Old   July 16, 2009, 17:56
Default
  #3
New Member
 
Valerio Novaresio
Join Date: Mar 2009
Location: Polonghera, Cuneo, Italy
Posts: 27
Rep Power: 8
novyno is on a distinguished road
Thanks... I have tried this solution yet, but the problem is that updateCoeff() is called every iteration and I don't know how I can block it!

Thanks for you reply...
__________________
...The best way to acquire new knowledge is to share it...
novyno 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
inlet velocity boundary condition murali CFX 5 August 3, 2012 08:56
spanwiperiodic boundary condition for LES Sungho Yoon CFX 5 July 8, 2008 06:21
How to set boundary condition in Fluent for the fo Peiyong FLUENT 1 November 10, 2006 12:44
Help Urgent about changing boundary condition Anjum Naveed FLUENT 7 August 14, 2006 12:25
1 and 2 Order Boundary condition at the same place CFD_Flo Main CFD Forum 4 July 11, 2005 11:57


All times are GMT -4. The time now is 15:22.