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

Residence time

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 2, 2005, 07:14
Default Residence time
  #1
AlwaysLearning
Guest
 
Posts: n/a
Hi Guys,

I am trying to calc the residence time in a simple domain. Cuboid, one inlet (supply) one outlet.

Isothermal, Ke and incompressible.

I am trying three things. No real joy.

To start with.

Path lines (set from interior (fluid)) gives a max rtd of 6.07 secs Particale tracks, (I set an injection of Carbon dioxide thoughout all fluid) gives 2.8 secs.

Why the difference?

I am also trying a UDS/UDF as suggested on the fluent site. Here I set a UDS. Set its value at 0 at inlet.

Copy the UDF and use that for the rt_source calc. as below.

DEFINE_SOURCE(rt_source,c,t,dS,eqn) { real source = C_R(c,t); dS[eqn] = 0.0; return source; }

Yet with this I don't get any RTD?

I get a uniform distribution of zero!

Ideas?

Thanks

  Reply With Quote

Old   September 2, 2005, 07:22
Default Residence time -sorry meant for fluent
  #2
AlwaysLearning
Guest
 
Posts: n/a
Sorry Guys,

The RTD calc was meant for the fluent forum. Perhaps I now need a rest!

  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
Upgraded from Karmic Koala 9.10 to Lucid Lynx10.04.3 bookie56 OpenFOAM Installation 8 August 13, 2011 05:03
calculation the residence time distribution by CFX ahmedsalemy CFX 4 June 25, 2009 11:40
IcoFoam parallel woes msrinath80 OpenFOAM Running, Solving & CFD 9 July 22, 2007 03:58
Residence time distribution function Roustam Phoenics 3 February 26, 2002 09:47
residence time Sugen Chetty Main CFD Forum 0 January 28, 2002 10:50


All times are GMT -4. The time now is 04:31.