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

MULTIGRID

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 21, 2007, 13:34
Default MULTIGRID
  #1
Tiz
Guest
 
Posts: n/a
Hello everyone,

I am try to apply multigrid to a 2D Navier-Stokes Finite Volume solver. Although I am looking for a steady state solution, I solve the problem with a time marching approach. I manage to code the problem in a 1d simpler case, but moving to the 2d proved more complex than I thought. Any suggestions on how to do this?

Thanks in advance

P.S. I obtained the adjoint equation for the coarser grid. Once linearised, this looks very similar to the equation solved in the fine grid, but the coefficients are now multiplied by the corrections rather than by the actual variables. Everything works well in 1D, but I have serious troubles in 2D
  Reply With Quote

Old   July 22, 2007, 00:23
Default Re: MULTIGRID
  #2
student
Guest
 
Posts: n/a
are you solving linear or non linear equation. and what type of problem are you solving.
  Reply With Quote

Old   July 22, 2007, 05:40
Default Re: MULTIGRID
  #3
Tiz
Guest
 
Posts: n/a
I am solving the full Navier-Stokes equations in a tube with a time marching approach. Of course this means nn linear equations ...
  Reply With Quote

Old   July 22, 2007, 16:07
Default Re: MULTIGRID
  #4
dontknow
Guest
 
Posts: n/a
Hi,

I recommend the paper by Raw: A coupled AMG fpr the 3D Navier-Stokes equations. It is a rather simple AMG which I also implemented. It is not based on very subtle mathematical approximation but on physical conservation properties. It is one of the most useful papers I ever read! Also the Algebraic Multigrid Tutorial by Briggs, Cormick and Henson is a very good literature about multigrid methods. Further the page www.mgnet.org.

Hope, this helps...
  Reply With Quote

Old   July 23, 2007, 08:48
Default Re: MULTIGRID
  #5
Tiz
Guest
 
Posts: n/a
Actually I am trying to use geometric multigrid rather than algebraic ... do you have a copy of the paper? Could you please send it to me?

Thanks
  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
LES by Multigrid mnabi Main CFD Forum 8 July 11, 2009 20:21
multigrid sureshkumar Main CFD Forum 0 June 9, 2006 01:20
Multigrid method Suresh kumar Main CFD Forum 1 April 24, 2006 20:07
MULTIGRID at the wall Jim Main CFD Forum 0 February 19, 2003 13:22
Multigrid applied to k-e models Paulo Zandonade Main CFD Forum 9 May 24, 1999 08:10


All times are GMT -4. The time now is 13:59.