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

Referece Area of 2D Airfoil

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

Reply
 
LinkBack Thread Tools Display Modes
Old   September 16, 2009, 03:55
Default Referece Area of 2D Airfoil
  #1
New Member
 
Join Date: Apr 2009
Posts: 17
Rep Power: 8
walex is on a distinguished road
Hi everybody,

can somebody tell me how the reference area is determined in OF 1.5? Until now I used the chordlength * mesh-extrusion in z direction. But I am not sure as my calculated Cd and Cl values are defnitely wrong.

Thanks
Alex
walex is offline   Reply With Quote

Old   September 16, 2009, 04:48
Default
  #2
New Member
 
Join Date: Apr 2009
Posts: 17
Rep Power: 8
walex is on a distinguished road
Hi,

to avoid any misunderstanding: Th question could also be for which area OF does calculate the forces? (2D)

Alex
walex is offline   Reply With Quote

Old   September 16, 2009, 16:42
Default
  #3
Senior Member
 
Steve Hansel
Join Date: Jun 2009
Location: Colorado, USA
Posts: 112
Rep Power: 8
hansel is on a distinguished road
My impression was that openfoam calculates the forces on all faces of the object and vector sums them. Then divides the drag vector and lift vectors by density, U^2 and the reference area that you specified to get Cd and Cl.

I believe chord_length * wing_length is the standard equation for wing reference area.

For objects other than wings, the reference area for drag is usually the area that the wind 'sees', but when it comes to wings, its the same area as for lift.


I don't think it's your reference_area that's wrong, I think it's the forces coming out of the simulation
.
hansel is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Low Speed Airfoil Mancusi FLUENT 7 April 3, 2014 06:11
Modeling Backflow for a 3D Airfoil (Wing of Finite Span) Josh CFX 9 August 18, 2009 11:31
Airfoil boundary condition Frank Main CFD Forum 1 April 21, 2008 18:36
CFX Solver Memory Error mike CFX 1 March 19, 2008 08:22
Storing Surface Area of each cell in a file? Markus Alzon FLUENT 0 June 21, 2007 08:38


All times are GMT -4. The time now is 09:21.