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

Highest lift coefficient

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 29, 2000, 03:26
Default Highest lift coefficient
  #1
Mark Render
Guest
 
Posts: n/a
I'm am looking for an airfoil shape (without flaps etc.) with a very high max. lift coefficient. Obviously the ratio of lift to drag coefficient should be high as well in that point. Is there an 'ultimative' airfoil shape ?

Mark
  Reply With Quote

Old   February 29, 2000, 04:09
Default Re: Highest lift coefficient
  #2
Johan Schulten
Guest
 
Posts: n/a
Hello Mark, Yes, there exists such a thing and it is called a Liebeck airfoil after its originator. The most complete reference I know is AIAA Paper 76-406 "On the Design of Subsonic Airfoils for High Lift" by Robert H. Liebeck. You can also look in "High-Lift Aerodynamics" by A.M.O. Smith, Journal Of Aircraft, Vol.12, No.6, June 1975, pp.501-530 or: "A Class of Airfoils Designed for High Lift in Incompressible Flow" by Robert H. Liebeck, Journal of Aircraft, Vol.10, No.10, Oct. 1973, pp.610-617. The theoretical maximum Cl for a single element airfoil at a Reynolds number of 5x10^6 is 3.06 with a lift to drag ratio of 600!
  Reply With Quote

Old   March 2, 2000, 02:38
Default Re: Highest lift coefficient
  #3
low
Guest
 
Posts: n/a
Read the articles introduced from Johan. For highest lift, from my experience, one should modify the shape of an original airfoil such as introduce stepwise discontinuity on the airfoil.
  Reply With Quote

Old   March 2, 2000, 04:39
Default Re: Highest lift coefficient
  #4
Mark Render
Guest
 
Posts: n/a
Could you explain in more detail what you mean by that ?

Mark
  Reply With Quote

Old   March 2, 2000, 09:02
Default Re: Highest lift coefficient
  #5
Tim Franke
Guest
 
Posts: n/a
Hi Johan,

haven't read these papers I guess that this airfoil is not symmetric. Do you know a high lift single element airfoil that is symmetric ?

Thanks in advance,

Tim
  Reply With Quote

Old   March 2, 2000, 09:30
Default Re: Highest lift coefficient
  #6
Johan Schulten
Guest
 
Posts: n/a
Hello Tim,

Yes, the Liebeck airfoils are highly cambered to achieve high lift at low drag. To me it seems rather contradictory to speak of a symmetric high lift airfoil. If I may rephrase your question to: "What would be the highest lift for a symmetric airfoil?", I can refer you to the Resources\References\Airfoils of this Website. A maximum Cl of 1.6 [NACA 0012] is typical for symmetric airfoils of moderate thickness.
  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
Lift coefficient in Eulerian multiphase model hennas FLUENT 1 July 4, 2011 17:50
Automotive test case vinz OpenFOAM Running, Solving & CFD 98 October 27, 2008 10:43
Zero Coefficient of Lift Problem MH FLUENT 0 February 25, 2007 12:48
Lift force or coefficient of lift Rola FLUENT 1 November 12, 2006 14:29
Help needed - lift coefficient on front/rear axle Jan Jagrik FLUENT 0 September 21, 2000 11:21


All times are GMT -4. The time now is 04:47.