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

buoyancy force due to concentration difference

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 8, 2005, 09:57
Default buoyancy force due to concentration difference
  #1
arsei0707
Guest
 
Posts: n/a
I'm confused that in my sloving problem there is a gas-moisture mixture with combined thermal and concentration force in my momentum equation. However, when I validate my problem by using a published paper which is a double diffusive cavity, I can't get the exact profiles whatever streamlin, isothermal line, and iso-concentration in aiding or opposing buoyany flow. Therefore, I begin check the pure thermal buoyancy driven flow in a square cavity, and a pure concentration byoyancy driven flow. However, in a pure thermal buoyancy driven flow, I can get a similar velocity and temperature distribution. But, in a pure concentration difference flow within a square cavity, there is no flow driven in my cavity.

Therefore, how can I turn on or add my buoyancy force due to concentration difference to get a combined gas-moisture problem when the Boussinesq approximation is valid.
  Reply With Quote

Old   December 14, 2005, 05:11
Default Re: buoyancy force due to concentration difference
  #2
Mike
Guest
 
Posts: n/a
As I recall the Buossinesq buoyancy force provided as an option in PHOENICS is a function of temperature difference only. Are you using this option? Or have you implemented your own buoyancy source term as a function of both temperature and concentration difference? It seems to me that you must do the latter either by use of the INFORM facility or by use of GROUND coding.
  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
Drag force difference between Solver and Post Dre CFX 2 November 21, 2008 12:02
Urgently Need the code of Lift force and VM force Kai Yan Main CFD Forum 0 July 16, 2008 07:07
MRFZonesC questions what is the mesh_V and why only Coriolis force no centrifugal force waynezw0618 OpenFOAM Running, Solving & CFD 49 April 8, 2008 04:23
Buoyancy production for species concentration George Gerber FLUENT 1 May 25, 2006 16:56
how to calculate prssure force & lift force in CFX zaidun CFX 4 March 28, 2006 01:06


All times are GMT -4. The time now is 19:27.