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

Difficulty in understanding Coeff. of Drag of Airfoil

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 9, 2017, 02:38
Default Difficulty in understanding Coeff. of Drag of Airfoil
  #1
New Member
 
Maharshi
Join Date: Mar 2017
Posts: 6
Rep Power: 5
Mhrc is on a distinguished road
Dear all,

I am finding difficulty in understanding the Coeff. of Drag and lift of a wing whose cross section is derived from Althaus AH 79-100A airfoil(link for coordinate file - https://m-selig.ae.illinois.edu/ads/coord/ah79100a.dat). The simulation was done in Star CCM+ R9 . The values obtained were,
Cd = 0.2811885068982537
Cl = 5.196364470423872
The dimensions of the wing are
Wing span (s) = 0.85417 m
Wing chord (c) = 0.0982m
Aspect ratio (AR) = 8.7
Angle of attack = 0 degrees
Air velocity = 30 m/s

Regarding mesh and physics continua

Mesh Base size = 0.014(prism layers and vol. controls were employed around wing body)
Physics model - K-epsilon.

My doubt is that whether the values obtained are correct or resemble to real time values and if so then why the Cd is so high?(i have attached the picture of the domain and wing so that you can have better understanding).If the values are not justifiable then what may be the possible causes of error.
Thank you in advance and your help is really appreciated.
Attached Images
File Type: png domain.png (27.8 KB, 13 views)
Mhrc 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
Airfoil lift and drag understimated Kio OpenFOAM Pre-Processing 15 October 1, 2016 14:48
Airfoil lift and drag using k-kl-omega turbulence model hylleman OpenFOAM Running, Solving & CFD 6 June 17, 2016 16:10
negative airfoil drag?? Robin FLUENT 4 January 7, 2010 17:29
calculating drag at low Re no over FX airfoil M. Essuri FLUENT 1 November 1, 2006 16:55


All times are GMT -4. The time now is 22:56.