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

solving moving airfoil flows at Re=5X10^4

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

Reply
 
LinkBack Thread Tools Display Modes
Old   August 18, 2005, 21:52
Default solving moving airfoil flows at Re=5X10^4
  #1
quarkz
Guest
 
Posts: n/a
Hi,

I need to solve a moving (flapping) airfoil in 2d at Re between 2X10^4 - 1X10^5. mainly to get lift/drag. how should i approach it?

should i be using dns? Will it take months?

or should i be using RANS/LES with some turbulence models? in that case, what would be a suitable one?

Can some experts here give their view?

Thank you!
  Reply With Quote

Old   August 19, 2005, 15:08
Default Re: solving moving airfoil flows at Re=5X10^4
  #2
Adrin Gharakhani
Guest
 
Posts: n/a
If it is incompressible flow vortex methods would be ideal for this problem (you can do low resolution DNS at this Reynolds number range with no problem).

Adrin Gharakhani
  Reply With Quote

Old   August 22, 2005, 07:08
Default Re: solving moving airfoil flows at Re=5X10^4
  #3
Suriyanarayanan
Guest
 
Posts: n/a
hi,

Flapping aerofoil problems at reynold numbers of 10^6 have been solved using RANS, even with 0- equation model to reasonable accuracy, so yours should not be a problem. I suggest the spallart and allmaras or MENTER - SST as a good RANS model for your problem. However the most important thing to be noted is the amplitude of oscillation. While RANS models work reasonbly well for attached and light stall cases they fail miserably for deep stall cases. For deep stall perform LES or DNS.

You can get solutions in a matter of hrs depending on the type of method that you would be employing. Infact, using dual time stepping with convergence acceleration devices reduces the time to nearly half a day.It is a luxury for unsteady computations.

Suriya

  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
Orifice Plate with a fully developed flow - Problems with convergence jonmec OpenFOAM Running, Solving & CFD 3 July 28, 2011 05:24
MRFSimpleFOAM goes divergenced! renyun0511 OpenFOAM Running, Solving & CFD 0 November 19, 2009 03:11
ForcesCoeffs ronaldo OpenFOAM 4 September 14, 2009 07:11
MRFSimpleFoam amp cyclic patches david OpenFOAM Running, Solving & CFD 36 October 21, 2008 21:55
IcoFoam parallel woes msrinath80 OpenFOAM Running, Solving & CFD 9 July 22, 2007 02:58


All times are GMT -4. The time now is 21:39.