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

multigrid blues

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 29, 2005, 05:45
Default multigrid blues
  #1
parth
Guest
 
Posts: n/a
Hello all, I am trying to write a code for FullMultigrid , I have a small doubt, When performing relaxation on coarser level , the equations are:

A_p x Phi_p + Sum( A_l x Phi_l) = Src_p + AdditionalSource;

AdditionalSource = (A_p x Phi_p + Sum( A_l x Phi_l) -Src_p)_by_restrictedvalues -restricted_Residual,

This remains fixed during this sweep.

Then I transfer my values to further coarser level.

Now my doubt is, what shall I do , when I transfer the correction back to finer level from coarser level. I mean the corrections are transferred and I have now the new values of the variables.And I shall do _post_relaxation_sweeps_ here, but what happens to this restricted_Residual, required in the additional source.

I am confused about this value. How do we construct the equation now for _post_relaxation_sweeps_????

Do I use the last restricted_Residual value (calculated when transferring from fine to coarse),

And what about the fluxes on the faces, how do we get them when we want to do post_relaxation_sweeps_ , do I calculate them from these corrected values?

  Reply With Quote

Old   April 1, 2005, 06:33
Default Re: multigrid blues
  #2
versi
Guest
 
Posts: n/a
You can keep the last restricted_Residual value (calculated when transferring from fine to coarse) during the upward sweep (the upward sweep refers the one from coarse to fine) But the fluxes need to be calculated again in the up sweep.
  Reply With Quote

Old   April 1, 2005, 07:24
Default Re: multigrid blues
  #3
parth
Guest
 
Posts: n/a
thanks for your reply, i really appreciate,

so when the variables(u v w p) are corrected the fluxes are calculated again based on corrected values,

and when the we go fine to coarse, the fluxes the same as of finer level (after restriction) ..correct??
  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
LES by Multigrid mnabi Main CFD Forum 8 July 11, 2009 21:21
multigrid sureshkumar Main CFD Forum 0 June 9, 2006 02:20
Multigrid method Suresh kumar Main CFD Forum 1 April 24, 2006 21:07
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 09:10


All times are GMT -4. The time now is 23:35.