CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Verification & Validation

twoLiquidMixingFoam: validation

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 8, 2014, 18:50
Default twoLiquidMixingFoam: validation
  #1
Member
 
xxxxx
Join Date: Feb 2013
Posts: 34
Rep Power: 13
xxxx is on a distinguished road
Hello everybody.
I'm trying to learn how twoLiquidMixingFoam works and also how fine the solution is, so I run a very simple test case, reproducing famous experiment by Reynolds.
In order to see if the solver works properly, I imposed a zero diffusivity between the two species and a laminar flow (turbulence off, Dt ab =0). Re number is around 100 and the duct is quite short.
In my opinion this should mean that the two liquid are completely non-miscible and so the should be transported w/o any mixing, i.e. the transport equation becomes:

ddt(alpha1)+div(phi,alpha1) == 0

What I actually got looks quite strange to me. I attached a picture of the solution. As you can see, there's a wide region of mixing between the two liquids.
On the other hand, I implemented a steady state transport eq in simple algorithm ( div(phi,a) == 0 ) and solved a similar case ("a" is a non-reactive non-diffusive passively transported scalar used as a marker. In that case I actually got that "a" is simply transported w/o mixing, as I supposed.

The case definition is attached .

Can you please help me? Am I wrong or is it a solver fault?

Thank you in advance

Federico
Attached Images
File Type: jpg 2liqMix.jpg (71.2 KB, 64 views)
File Type: jpg alpha1.jpg (49.7 KB, 56 views)
Attached Files
File Type: zip 2liq.zip (9.3 KB, 15 views)
__________________
Federico
xxxx is offline   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
Validation in Transient tasks MaxakCh FLUENT 0 May 17, 2013 09:59
CFX problem in ubuntu (linux) Vigneshramaero CFX 0 July 13, 2012 11:22
CFX-Pre problem, pls help!!! cth_yao CFX 0 February 17, 2012 01:52
Validation test for 2d euler equations in subsonic regime with canonical squares panou Main CFD Forum 2 August 24, 2011 16:21
Urgent: RAE 2822 validation NID Main CFD Forum 0 September 3, 2004 11:34


All times are GMT -4. The time now is 08:03.