CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

Implicit density pressure relation

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 19, 2008, 05:15
Default Good Morning everyone, i wo
  #1
caw
Member
 
Christian Winkler
Join Date: Mar 2009
Location: Mannheim, Germany
Posts: 63
Rep Power: 8
caw is on a distinguished road
Good Morning everyone,

i would like to add a new density pressure relation to a compressible solver (low Ma-Number, isothermal, laminar Flow). It looks like:

rho = p * 1/(A + Bp) // A and B are constants

Problem:
all compressible solvers in OF use a linear relation for compressibility (unless i missed something).

-> psi = drho/dp
With this, my psi would be a function of p, which is not allowed in the pressure equation.

Does anyone out there managed to solve a similar problem or could give me some hints about literature for this kind of pressure equations?

Thanks and best regards
Christian
caw is offline   Reply With Quote

Old   April 23, 2008, 23:30
Default Christian, How about recalcul
  #2
Member
 
David P. Schmidt
Join Date: Mar 2009
Posts: 70
Rep Power: 8
schmidt_d is on a distinguished road
Christian,
How about recalculating psi every PISO iteration using the latest available pressure? Psi would be slightly lagged, but if B is not too large, I think it would work.
-DPS
schmidt_d is offline   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
negative density/pressure littlelz Main CFD Forum 5 May 13, 2008 00:36
Density as a function of Pressure asder CFX 8 April 10, 2008 19:14
Density Relation for Hydrogen Mixing Shariff CD-adapco 0 August 3, 2006 10:48
2D vs 3D in relation to pressure gradient Isa Main CFD Forum 0 May 18, 2006 03:38
FEM pressure poisson equation (Implicit) cfd-beginner Main CFD Forum 0 August 9, 2005 13:32


All times are GMT -4. The time now is 06:18.