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

General question what fluid properties do you use

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 18, 2008, 16:38
Default Hi, I have a question: I
  #1
Member
 
Daniel Harlacher
Join Date: Mar 2009
Location: Davis, CA, United States
Posts: 60
Rep Power: 17
harly is on a distinguished road
Hi,

I have a question:

I am trying to evaluate lift/drag from a square cylinder and I am struggling with the results I get.

I read that OpenFOAM produces fairly good results for such problems - but I also read, that OpenFOAM gives best results "dimensionfree" - and therefore most of the people are using v=1 and nu = "equivalent to get wanted Re number".

I need to use properties of air to be able to compare my results.

so I picked

Ux = 0.3

nu = 1.5e-5

and in forces/forceCoeffs(to calculate lift/drag in OF1.5)
rho = 1.2

equals Re = 20000

But my results are very bad, e.g Lift more than twice as it should be.
Any Ideas? What properties do you use for air ? And how do you get the right Coefficients ?
Thanks
harly 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
A general C question niklas OpenFOAM 1 September 8, 2008 12:38
general question Madhukar Rapaka FLUENT 1 June 28, 2006 09:03
General Question vcoralic OpenFOAM Running, Solving & CFD 0 June 13, 2006 05:24
General CFD question hani Main CFD Forum 0 March 13, 2003 08:27
General CFD Question sam kashan Main CFD Forum 15 June 18, 2002 10:21


All times are GMT -4. The time now is 03:57.