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

Iterative solution to Poissons Equation

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   December 8, 2010, 13:28
Default Iterative solution to Poissons Equation
  #1
New Member
 
Philip Piper
Join Date: Oct 2010
Posts: 12
Rep Power: 16
Phiper is on a distinguished road
Can someone please explain either the SOR iterative solution to Poissons Equation or any other that may be faster? I'm having trouble wrapping my head around the concept of how this equation can be used to create a mass-conserving field. Thanks for any help!!!

**Edit: Or link me to any explanations or previous threads
Phiper is offline   Reply With Quote

Old   December 8, 2010, 14:42
Default
  #2
Member
 
Dan
Join Date: Oct 2010
Location: UK
Posts: 41
Rep Power: 16
dandalf is on a distinguished road
I have attached a quick derrivation of the pressure poisson equation, I hope this explains how it maintains conservation of mass.

The pressure requirements at physical boundaries can also be derrived useing similar methods,

As for solvers, I have been using a direct itterative Gauss -Seidel method, although I would welcome any sugestions for an alternative.
Attached Files
File Type: pdf PressureShort.pdf (88.7 KB, 39 views)
dandalf is offline   Reply With Quote

Old   December 9, 2010, 16:01
Default
  #3
Senior Member
 
TWB
Join Date: Mar 2009
Posts: 414
Rep Power: 19
quarkz is on a distinguished road
Are you trying to solve the Poisson eqn? You can try multigrid which is very suitable for Poisson eqn. PETSc and hypre can be used together to solve your Poisson eqn.
quarkz is offline   Reply With Quote

Old   December 9, 2010, 19:58
Default
  #4
New Member
 
Philip Piper
Join Date: Oct 2010
Posts: 12
Rep Power: 16
Phiper is on a distinguished road
Yes I've heard of multigrid before. I just don't understand how it works. And I've looked at a few explanations online but i havn't really found them satisfactory.
Phiper is offline   Reply With Quote

Old   December 10, 2010, 02:58
Default
  #5
New Member
 
Alexey
Join Date: May 2009
Location: St.Petersburg, Russia
Posts: 23
Rep Power: 17
ignat is on a distinguished road
Quote:
Originally Posted by Phiper View Post
Can someone please explain either the SOR iterative solution to Poissons Equation or any other that may be faster?
I think conjugate gradient method with preconditioner is faster then SOR.
I recommended to use Saad's SPARSKIT library, see here
http://www-users.cs.umn.edu/~saad/so...KIT/index.html
ignat is offline   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
Analytical solution of poisson equation kostaspan Main CFD Forum 1 April 22, 2010 13:24
Does FOAM converge to exact solution in Laplace equation? santiagomarquezd OpenFOAM Running, Solving & CFD 0 March 26, 2010 08:52
Viscosity and the Energy Equation Rich Main CFD Forum 0 December 16, 2009 15:01
IcoFoam parallel woes msrinath80 OpenFOAM Running, Solving & CFD 9 July 22, 2007 03:58
solution to Burger's Equation using fortran Tony Limjuco Main CFD Forum 4 April 2, 2005 01:41


All times are GMT -4. The time now is 17:15.