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

Discretization

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 22, 2003, 11:55
Default Discretization
  #1
Christian
Guest
 
Posts: n/a
Does anyone know when Fluent does a 1.st order approx. if it is a forward or backward step?

And I guess that when using 2.order it is a central difference?

Cheers and a merry christmas and a happy new year to all.
  Reply With Quote

Old   December 22, 2003, 12:36
Default Re: Discretization
  #2
ap
Guest
 
Posts: n/a
Both 1st order and 2nd order schemes are "upwind".

Second order scheme uses central differences.

Hi and Merry Christmas

ap
  Reply With Quote

Old   December 23, 2003, 15:54
Default Re: Discretization
  #3
Jun
Guest
 
Posts: n/a
Agree on the first statement--"both 1st order and 2 nd order schemes are upwind.". The second statement is confusing. Central difference is only applicable for the convection term when using LES in fluent as I found from the fluent manual. Am I right?

Have a nice holiday!

Jun
  Reply With Quote

Old   December 23, 2003, 17:38
Default Re: Discretization
  #4
ap
Guest
 
Posts: n/a
When you choose a discretization scheme in the Solve->Controls->Solution panel, that scheme will be used only to compute the convective term of the corresponding equation.

On the second order scheme, FLUENT manual says (. 24.2.3) that higher-order accuracy is achieved at cell faces through a Taylor series expansion of the cell-centered solution about the cell centroid. The variable and the gradient are cell centered, while the displacement vector is from the upstream cell centroid to the face centroid.

Hi and Merry Christmas

ap
  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
Convergence and discretization karananand FLUENT 3 August 29, 2010 06:07
Discretization and convergence karananand Main CFD Forum 0 August 4, 2010 16:19
Space and time discretization of Euler equation Hooman Main CFD Forum 2 June 6, 2010 08:30
Spatial vs Angular Discretization in DO radiation model renaldi FLUENT 0 June 1, 2009 10:52
Low-Re and second order discretization Ralf CD-adapco 1 May 11, 2006 10:16


All times are GMT -4. The time now is 21:39.