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

Bubble size for eulerian model

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 28, 2010, 00:49
Default Bubble size for eulerian model
  #1
Senior Member
 
karine
Join Date: Nov 2009
Posts: 158
Rep Power: 7
thecfduser is on a distinguished road
Hi dear colleagues,
i am using Fluent to simulate a vertical separator.

In the bottom part of the separator, i have liquid as continuous phase with a free vortex on the interface, and some bubbles (not a lot)
In the upper part, i have gas as continuous phase with some liquid droplets
(not a lot also)

I cant use VOF because the phases are not clearly separated (bubbles and liquid droplets near the interface). I tried it and the results are very bad.

So, for simulating it in Fluent, i need to use an eulerian model. The problem is that the model needs a particle size for bubbles (or droplets) to calculate drag, and the results will depends on this size.
As i dont have any reprsentattive bubble size (or droplet size) in my flow, how must i choose this dimension???

Thanks a lot for ure help
thecfduser is offline   Reply With Quote

Old   April 28, 2010, 11:09
Default
  #2
New Member
 
Ling
Join Date: Jun 2009
Posts: 25
Rep Power: 8
nstar is on a distinguished road
My colleague had the exact problem before. He looked for my suggestion since I was working on boiling, supposed to be knowing bubbles. However I could not answer his question.
I'd suggest to do some literature review

Quote:
Originally Posted by thecfduser View Post
Hi dear colleagues,
i am using Fluent to simulate a vertical separator.

In the bottom part of the separator, i have liquid as continuous phase with a free vortex on the interface, and some bubbles (not a lot)
In the upper part, i have gas as continuous phase with some liquid droplets
(not a lot also)

I cant use VOF because the phases are not clearly separated (bubbles and liquid droplets near the interface). I tried it and the results are very bad.

So, for simulating it in Fluent, i need to use an eulerian model. The problem is that the model needs a particle size for bubbles (or droplets) to calculate drag, and the results will depends on this size.
As i dont have any reprsentattive bubble size (or droplet size) in my flow, how must i choose this dimension???

Thanks a lot for ure help
nstar 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
Single Bubble Gerrit Senger CFX 4 March 12, 2007 17:29
Particle size in Eulerian Multiphase Model. guru FLUENT 2 January 10, 2005 06:01
how to difine bubble size? major FLUENT 0 November 19, 2004 03:00
Time Step Size for Airfoil Model - Fluent Prateek Main CFD Forum 0 November 4, 2004 19:42
size of first cell near wall for k-epselon model mukkarum FLUENT 3 May 11, 2004 04:10


All times are GMT -4. The time now is 18:56.