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

Mathematical derivation of SIMPLE etc.

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

Like Tree1Likes
  • 1 Post By RodriguezFatz

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   December 18, 2013, 03:28
Default Mathematical derivation of SIMPLE etc.
  #1
New Member
 
Join Date: Jan 2013
Posts: 17
Rep Power: 13
Za-ck is on a distinguished road
Hi,

are the any mathematical derivations/proofs which show that the algorithms like SIMPLE/SIMPLER/PISO are working? I can only find the original papers but I don't like to buy them till I know that this mathematical stuff is included.

Best Regards,

Za-ck
Za-ck is offline   Reply With Quote

Old   December 18, 2013, 09:38
Default
  #2
Senior Member
 
RodriguezFatz's Avatar
 
Philipp
Join Date: Jun 2011
Location: Germany
Posts: 1,297
Rep Power: 26
RodriguezFatz will become famous soon enough
I don't think there are any proofs. Like all other non-linear solvers (at least that I know) I think you can not show that they converge for every case. As far as I know, this (showing convergence) only works with really simple cases, such as linear problems.
__________________
The skeleton ran out of shampoo in the shower.

Last edited by RodriguezFatz; December 19, 2013 at 04:09.
RodriguezFatz is offline   Reply With Quote

Old   December 18, 2013, 10:40
Default
  #3
New Member
 
Join Date: May 2013
Posts: 12
Rep Power: 12
levivad is on a distinguished road
I don't know about the specific algorithms above, but YOU CAN show stability and convergence for nonlinear solvers.
In fact I'm pretty sure you must show stability and convergence of any new solver.
CFX for example is unconditionally stable///
levivad is offline   Reply With Quote

Old   December 19, 2013, 04:13
Default
  #4
Senior Member
 
RodriguezFatz's Avatar
 
Philipp
Join Date: Jun 2011
Location: Germany
Posts: 1,297
Rep Power: 26
RodriguezFatz will become famous soon enough
Quote:
Originally Posted by levivad View Post
CFX for example is unconditionally stable///
This statement does not make any sense. CFX is a software tool with tons of different numerical methods.
Please go to CFX and set under relaxation factor for pressure to 100 in SIMPLE. See what happens.
deepak.kn1990 likes this.
__________________
The skeleton ran out of shampoo in the shower.
RodriguezFatz is offline   Reply With Quote

Old   December 19, 2013, 04:49
Default
  #5
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,763
Rep Power: 71
FMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura about
Quote:
Originally Posted by Za-ck View Post
Hi,

are the any mathematical derivations/proofs which show that the algorithms like SIMPLE/SIMPLER/PISO are working? I can only find the original papers but I don't like to buy them till I know that this mathematical stuff is included.

Best Regards,

Za-ck

Could you better formulate your question? what do you mean with "are working"? Discrete formulations that are consistent and stable must always work ...
FMDenaro is online now   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
SIMPLE algorithm in 3D cylindrical coordinates zouchu Main CFD Forum 1 January 20, 2014 17:02
Simple approach - solid wood combustion (newbie..) Dan Main CFD Forum 0 December 3, 2007 02:06
derivation enthalpy Tomik FLUENT 2 March 9, 2006 15:39
shallow water and simple scheme AO Main CFD Forum 0 January 13, 2004 20:07
Help me on SIMPLE L. Aouanouk Main CFD Forum 6 April 17, 2003 05:08


All times are GMT -4. The time now is 05:57.