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

Mixing model with rotating impeller problem

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 23, 2010, 14:42
Default Mixing model with rotating impeller problem
  #1
201
New Member
 
uni hannover
Join Date: Mar 2010
Posts: 4
Rep Power: 16
201 is on a distinguished road
hi erveryone,
i have some problem my project. Mixing model with rotating impeller. the some problem i dont understand and how to repair that:

2 isolated fluid regions were found in the following set of
coupled domains:

R
S

If the isolated regions do not have the pressure level set either
by the boundary conditions or using a reference pressure equation,
you may encounter severe robustness problems.

This situation may have arisen because a domain interface was not
properly defined during problem setup. Please carefully check
the setup.

The solver will stop now and write a results file. The isolated
regions can be visualised in CFX Post by making plots of the
variable "Isolated Volumes".

If you are sure that the pressure level is set in each isolated
fluid region then you can force the solver to turn off this check
by setting the expert parameter "check isolated regions = f".
http://www.4shared.com/file/GNtjMbVv/model.html
201 is offline   Reply With Quote

Old   April 26, 2010, 09:10
Default
  #2
Senior Member
 
Attesz's Avatar
 
Attesz
Join Date: Mar 2009
Location: Munich
Posts: 368
Rep Power: 17
Attesz is an unknown quantity at this point
I think you should check your fluid interfaces.
Attesz is offline   Reply With Quote

Old   April 27, 2010, 10:55
Default
  #3
201
New Member
 
uni hannover
Join Date: Mar 2010
Posts: 4
Rep Power: 16
201 is on a distinguished road
please help me
201 is offline   Reply With Quote

Old   April 27, 2010, 19:32
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,871
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Attesz has said what the problem is - your interfaces are not correctly connecting the two domains so they end up being isolated.
ghorrocks is offline   Reply With Quote

Old   May 12, 2010, 17:59
Default
  #5
Senior Member
 
Join Date: Feb 2010
Posts: 148
Rep Power: 17
Jade M is on a distinguished road
----------

Last edited by Jade M; June 4, 2010 at 15:27.
Jade M is offline   Reply With Quote

Old   May 12, 2010, 18:15
Default
  #6
Senior Member
 
Attesz's Avatar
 
Attesz
Join Date: Mar 2009
Location: Munich
Posts: 368
Rep Power: 17
Attesz is an unknown quantity at this point
No! I recommend you to do the tutorials and read the basics in CFD. You should set the interface as a Fluid-Fluid Interface. This is a connection between the domains, opening and outlet are boundaries, they BOUND the domains, not connect.
Attesz is offline   Reply With Quote

Old   May 12, 2010, 18:18
Default
  #7
Senior Member
 
Join Date: Feb 2010
Posts: 148
Rep Power: 17
Jade M is on a distinguished road
Yes! Thanks for your quick reply! LOL. I have read the tutorials and manuals but thank you for the suggestion. Fluid-fluid interface is not an option. Perhaps the interface does not need to be explicitly defined?

Can anyone explain this more clearly?

Thank you.
Jade M is offline   Reply With Quote

Old   May 12, 2010, 18:49
Default
  #8
Senior Member
 
Attesz's Avatar
 
Attesz
Join Date: Mar 2009
Location: Munich
Posts: 368
Rep Power: 17
Attesz is an unknown quantity at this point
I can't understand you. You should define an interface, not a boundary condition. In the interface definition, you should set your fluid domains(you should have at least 2 pieces), and the regions, where they connect. It is very simple, and clearly discussed in the help.
Attesz is offline   Reply With Quote

Old   May 13, 2010, 09:48
Default
  #9
Senior Member
 
Join Date: Feb 2010
Posts: 148
Rep Power: 17
Jade M is on a distinguished road
----------

Last edited by Jade M; June 4, 2010 at 15:27.
Jade M is offline   Reply With Quote

Old   May 13, 2010, 11:19
Default
  #10
Senior Member
 
Attesz's Avatar
 
Attesz
Join Date: Mar 2009
Location: Munich
Posts: 368
Rep Power: 17
Attesz is an unknown quantity at this point
Please send some picture about your geom, with the interfaces marked, and a screenshot from your setting tree in CFX pre. Did you do the solver's message:

Otherwise, I wrote "I can't understand you" because I really can't understand what the problem is. If it would bother me, I really wouldn't reply

Quote:
How do you define an interface? The interface is already there due to multiple volumes. Is there something more that needs to be done?
If the interface connection isn't automatically generated, you should click on the Interface icon on the top, and set what do you need. Here Interface means a defined connection betweed fluid domains, which need to be automatically or manually adjust.

Last edited by Attesz; May 14, 2010 at 05:30.
Attesz is offline   Reply With Quote

Old   May 14, 2010, 12:59
Default
  #11
Senior Member
 
Join Date: Feb 2010
Posts: 148
Rep Power: 17
Jade M is on a distinguished road
Thanks Attesz. I found it in the menu. I was looking for the mechanics of using the software, as this is the first time that I've set up a multizone model. Take care.
Jade M is offline   Reply With Quote

Reply


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
Centrifugal Pump and Turbulence Model Michiel CFX 12 January 25, 2010 04:20
mass balance problem in multiphase model mdsanij1 FLUENT 0 July 28, 2009 17:01
Problem in Herschel-Bulkely model emad FLUENT 0 May 20, 2009 15:20
mixing model aravind FLUENT 0 November 14, 2008 04:51
Boundries of rotating impeller created in Gambit ? Mounir FLUENT 2 October 23, 2000 07:56


All times are GMT -4. The time now is 04:13.