+ Reply to Thread
Results 1 to 5 of 5

Thread: Drag Reduction by means of flow control over a surface

  1. #1
    Site Developer Jman's Avatar
    Join Date
    Oct 2002
    Location
    Pacific NW, USA!
    Posts
    2,387

    Drag Reduction by means of flow control over a surface

    Found and interesting article on Sciencedaily.com . I've posted a small teaser paragraph below.
    "The most promising actuators are the so called synthetic jet or oscillatory jet actuators which are embedded in the surface of the body (an airplane wing for example), and essentially perform injection and suction of the fluid from the surface in a periodic manner," said Agarwal. He has demonstrated that the transonic drag of an airplane wing can be reduced by 12 to 15 percent with the incorporation of three-ounce actuators, about 20 to 30 spaced optimally on the surface of the wing.

  2. #2
    Registered User GESchwarz's Avatar
    Join Date
    Oct 2007
    Location
    Ventura County, California, USofA.
    Posts
    1,009

    Re: Drag Reduction by means of flow control over a surface

    A related article linked to the same page Wings That Waggle Could Cut Aircraft Emissions By 20% speaks about a subject that was covered in this forum about a week ago. I'm thinking that this may be why birds were built with feathers.

    It almost makes you want to tar and feather your airplane.

    Seriously, these ideas may have merit.
    If you see something, say something.

  3. #3
    Registered User
    Join Date
    Nov 2007
    Posts
    886

    Re: Drag Reduction by means of flow control over a surface

    There was a great article by Peter Garrison relating to this in the September, 1990 Flying magazine. I enjoyed the article a lot, but I don't necessarily buy all of it. However, it is highly recommended. Not sure how you could find it, though.

  4. #4
    Moderator autoreply's Avatar
    Join Date
    Jul 2009
    Location
    Leiden, Netherlands
    Posts
    8,060

    Re: Drag Reduction by means of flow control over a surface

    Loek Boermans does a lot of research in it (low-speed only). It's extremely efficient (think 50% less drag on the most optimised profile possible), but in reality it's almost impossible to achieve since the holes are so tiny they are immidiately blocked by dust in a real-life environment. I'm afraid (and heard from others too) that this idea has less or more the same problem, it's a perfect solution, but might not work in reality because it's too tiny and too vulnerable (think -50 centigrade and some ice).

    Nice idea nevertheless, but realistic? I don't believe so..
    Last edited by autoreply; October 23rd, 2009 at 04:55 PM.

  5. #5
    Moderator Topaz's Avatar
    Join Date
    Jul 2005
    Location
    Orange County, California
    Posts
    8,209

    Re: Drag Reduction by means of flow control over a surface

    Surface blowing or suction in strategic locations has been known since the 1960's to give tremendous drag reduction. These schemes all fall down on the same basis that autoreply is talking about: whether slot or hole, keeping them clean and free of obstruction is virtually impossible in the real world. The weight penalty of all those holes (or slots) in the skin can also be substantial, since the skin loses some or all of its ability to resist twisting for the wing.
    "If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them." - Henry James Thoreau
    Member of the Lake Elsinore Soaring Club.

+ Reply to Thread

Similar Threads

  1. Conclusions on Aluminum Adhesive Bonding Tests
    By GESchwarz in forum Aircraft Design / Aerodynamics / New Technology
    Replies: 213
    Last Post: April 4th, 2014, 01:27 AM
  2. Bruce Carmichael's "drag reduction" book
    By gschuld in forum Aircraft Design / Aerodynamics / New Technology
    Replies: 24
    Last Post: December 20th, 2013, 03:24 PM
  3. Control surface hinge angles
    By addaon in forum Aircraft Design / Aerodynamics / New Technology
    Replies: 13
    Last Post: July 16th, 2009, 11:38 AM
  4. speed difference, fixed gear vs retracts
    By gschuld in forum Aircraft Design / Aerodynamics / New Technology
    Replies: 13
    Last Post: February 11th, 2009, 06:09 PM
  5. Control surface interference (aerodynamic)
    By Tinbuzzard in forum Aircraft Design / Aerodynamics / New Technology
    Replies: 5
    Last Post: March 18th, 2005, 11:33 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts