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

Multiphase Homogeneous Model equations

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 2, 2013, 14:09
Default Multiphase Homogeneous Model equations
  #1
Member
 
Marco Antonio
Join Date: Nov 2012
Posts: 46
Rep Power: 4
marcoymarc is on a distinguished road
Hello everybody,
i am struggling to find out the equations solved in a homogeneous model for both fluids.
Are NS solved for each fluid and a commonc velocity field is applied at interface? Exactly, which are the advantages of a euler-eluer vs lagrange model?
marcoymarc is offline   Reply With Quote

Old   July 2, 2013, 18:56
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,669
Rep Power: 84
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
In a homogenous model a single velocity and pressure field is solved, and the volume fraction equation is for which phase is where. The VF equation couples to the velocity and pressure equations by controlling density (along with any other coupling, eg surface tension).

In a inhomogenous model a velocity field is solved for each phase. This means at any point different phases can have different velocities - for instance tiny bubbles rising in a stationary liquid.

Both homo- and inhomogenous models are eularian models.

Lagrange models are totally different - they track bodies (eg particles, bubbles) in a lagrangian framework where each individual body is modelled, rather than a eularian framework where "stuff" is aggregated into control volumes, and you do conservation of "stuff" in control volumes.
ghorrocks is offline   Reply With Quote

Old   July 3, 2013, 09:10
Default
  #3
Member
 
Sebastian
Join Date: Apr 2013
Posts: 31
Rep Power: 4
Badi is on a distinguished road
CFX is using the euler-euler approach by default right? Does it have specific particle tracking method?
Badi is offline   Reply With Quote

Old   July 3, 2013, 19:11
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,669
Rep Power: 84
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
No, the eular-eular model and lagrangian models are completely separate. e-e is chosen when you go the homogeneous/inhomogeneous route, lagrangian is chosen when you go the particle tracking route.
ghorrocks 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
Implementation of Homogeneous Multiphase Model for Cavitation sfigato OpenFOAM Programming & Development 2 March 20, 2013 03:35
mixture model or multiphase model in my UDF? aleisia Fluent UDF and Scheme Programming 0 June 8, 2011 13:25
multiphase model, water in air? bugra Main CFD Forum 10 January 2, 2010 14:09
multiphase mixing Problem with MRF model in MixSim Srinivas FLUENT 0 October 17, 2005 06:35
multiphase model Sumeet FLUENT 2 August 31, 2005 08:26


All times are GMT -4. The time now is 22:49.