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

About Brackbill's Continuum Surface Force (CSF) model

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 5, 2010, 17:52
Question About Brackbill's Continuum Surface Force (CSF) model
  #1
New Member
 
James Zhong
Join Date: Mar 2009
Posts: 25
Rep Power: 17
James is on a distinguished road
I am attempting to use Brackbill's Continuum Surface Force (CSF) model to simulate surface tension in a free-surface flow. For my simulation, the time step constraint imposed by the explicit treatment of surface tension is too tight. The allowable time step is up to the scale of 10^-9 second. Does anyone know any references which use an implicit treatment of surface tension under the framework of CSF? Thanks!

James
James is offline   Reply With Quote

Old   August 7, 2010, 15:27
Default Csf
  #2
Super Moderator
 
Hans Bihs
Join Date: Jun 2009
Location: Trondheim, Norway
Posts: 375
Rep Power: 17
valgrinda is on a distinguished road
Hei James,

I also use the CSF method for free surface flow, but I don't experience such drastic constraints for the timestep. Maybe your code has an error. Depending on your formulation of your Navier-Stokes Equations, you may need to dived the surface tension source term by the density (or multiply with the volume, if you use the finite volume method).

Cheers Hans
valgrinda is offline   Reply With Quote

Old   August 9, 2010, 13:04
Default
  #3
New Member
 
James Zhong
Join Date: Mar 2009
Posts: 25
Rep Power: 17
James is on a distinguished road
valgrinda,
Thank you for your reply! I will double-check my code.

James
James is offline   Reply With Quote

Old   August 10, 2010, 13:12
Default
  #4
New Member
 
James Zhong
Join Date: Mar 2009
Posts: 25
Rep Power: 17
James is on a distinguished road
I noticed that in Brackbill's paper, the average density <Rho> = 0.5*(Rho1 + Rho2). In some other places, this density is taken as a volume averaged value. Which is way is good? Thanks!

James
James is offline   Reply With Quote

Old   August 23, 2010, 07:09
Default CSF Implementation
  #5
Super Moderator
 
Hans Bihs
Join Date: Jun 2009
Location: Trondheim, Norway
Posts: 375
Rep Power: 17
valgrinda is on a distinguished road
Hei James,

check this paper for the implementation of the CSF model:
http://wissrech.ins.uni-bonn.de/rese...er/droplet.pdf

Regards
Hans
valgrinda is offline   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
Continuum Surface Force Model Miguel Main CFD Forum 4 August 4, 2012 15:56
Surface roughness setting for a model in wind tunnel test section Sharon CFX 12 March 31, 2009 14:09
Surface tension - Continuum Surface Force model Robert Main CFD Forum 0 May 2, 2002 08:34
surface tension force Ray Main CFD Forum 0 October 17, 2001 16:42
gravitational force for free surface flow Jongtae Kim Main CFD Forum 1 July 2, 2000 12:57


All times are GMT -4. The time now is 07:14.