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

How can define different diffusion coefficients

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 21, 2010, 10:24
Default How can define different diffusion coefficients
  #1
Member
 
Frank Weise
Join Date: Mar 2009
Location: Germany
Posts: 55
Rep Power: 17
FrankW is on a distinguished road
Hi,

i will solve a fluidsystem (Water) with an porous domain. To simulate Oxygen transport in this system i use an Additional Variable. My problem is i can't define different diffusion coefficients in different domains. If i change in one domain the diffusion coeff. than is this cofficient in the other domain the same. What do i wrong or is't such possible.

best regards
Frank
FrankW is offline   Reply With Quote

Old   July 31, 2010, 10:43
Default
  #2
New Member
 
catherina
Join Date: May 2009
Posts: 7
Rep Power: 16
gypas is on a distinguished road
Don't know if you solved your problem yet there is a way of disabling constant physics in domains, actually there are a couple of threads describing how
http://www.cfd-online.com/Forums/cfx...s-cfx-pre.html
http://www.cfd-online.com/Forums/cfx...nt-domain.html
However, when I used this method the solver was very unstable and did not get accurate solutions.
Depending on the problem you are trying to model, you might be better off by assigning different fluids, values to different domains setting user parameters
for instance
domain 1 = domain1
domain 2 = domain2
fluid name1 = Water
fluid name2 = Vapor
but have not tried that myself
i only used user parameters in single flow simulation
I will be going back to multiphase domains later this year (beginning of November to be exact) and will discuss it in length with my support.
If by then you haven't sort it things out you are more than welcome to email me and I will give you further details.
gypas is offline   Reply With Quote

Reply

Tags
diffusion coefficient

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
Moving mesh Niklas Wikstrom (Wikstrom) OpenFOAM Running, Solving & CFD 122 June 15, 2014 07:20
Installing OF 1.6 on Mac OS X gschaider OpenFOAM Installation 129 June 19, 2010 10:23
Missing math.h header Travis FLUENT 4 January 15, 2009 12:48
Free surface boudary conditions with SOLA-VOF Fan Main CFD Forum 10 September 9, 2006 13:24
UDF FOR UNSTEADY TIME STEP mayur FLUENT 3 August 9, 2006 11:19


All times are GMT -4. The time now is 09:01.