---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Tue 01/22/13: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:01 PM - Micro Vortex Generators (N642K) 2. 03:00 PM - Re: Micro Vortex Generators (Warren Hill) 3. 03:04 PM - Re: Micro Vortex Generators (Bill Geipel) 4. 03:34 PM - Re: Micro Vortex Generators (cjpilot710@aol.com) 5. 05:37 PM - Re: Micro Vortex Generators (Roger Kemp M.D.) ________________________________ Message 1 _____________________________________ Time: 02:01:12 PM PST US Subject: Yak-List: Micro Vortex Generators From: "N642K" Anybody tried these? http://www.microaero.com/index.html Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392894#392894 ________________________________ Message 2 _____________________________________ Time: 03:00:31 PM PST US Subject: Re: Yak-List: Micro Vortex Generators From: Warren Hill Mike, Last year, I did a research project for my CJ-6A using this company's vortex generators, with the help of their flight test engineer. This involved placing vortex generators at various cord distances, along with a video tape assessment of the moment of a stall with tufting. This project was initially helped by the fact that the the CJ-6A wing root airfoil is pretty much the same as the Beechcraft Baron (NACA 23016.5) and the wing tip is similar to the NACA 2214 airfoil. With these airfoil designs in mind as a starting point, what we discovered is that for the main wing, with the vortex generators placed at a cord distance of 8.5%, the stall speed was reduced to 55 KIAS, clean. That's about 10%, which are me very happy. We also placed vortex generators on the undersurface of the horizontal stabilizer and on the vertical stabilizer. Once we decided on a specific distance for the VGs what the tufting video also demonstrated was that only the wing root stalled and the boundary layer remained completely intact from just before the beginning of the upward angle of the dihedral all the ay out to the wing tip. Of course, some of this is due to the wing twist, but the preservation of the boundary layer for such a large amount of the wing at 55 KIAS was impressive. What appeals to me about this is that placing vortex generators seems to have slightly extended the back part of the power curve an unhappy place where trouble may follow. The airplane also appears to have a little more rudder authority at slower airspeeds. I have no proof of this just my impression during takeoff and landing. The VGs certainly make the leading edge a lot more difficult to clean, but that's a small thing. If anyone wants to duplicate these efforts, feel free to contact me off-line. Warren Hill Mesa, AZ k7wx@earthlink.net On Jan 22, 2013, at 2:58 PM, N642K wrote: > > Anybody tried these? http://www.microaero.com/index.html > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=392894#392894 > > > > > > > > > > ________________________________ Message 3 _____________________________________ Time: 03:04:44 PM PST US Subject: Re: Yak-List: Micro Vortex Generators From: Bill Geipel I've had a set in the box for 12 years. Maybe it's time. Just a thought. Bill On Jan 22, 2013, at 2:58 PM, "N642K" wrote: > > Anybody tried these? http://www.microaero.com/index.html > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=392894#392894 > > > > > > > > > > ________________________________ Message 4 _____________________________________ Time: 03:34:27 PM PST US From: cjpilot710@aol.com Subject: Re: Yak-List: Micro Vortex Generators I have not done it on CJ-6. however the airfoil on the CJ is the same as the T-34/Bonanza (NASA 23015/4422 at the tip). Whatever % of performance those airplanes realized will most likely show up on the CJ. The Yak has Clark Y airfoils. I do not know what would show up on those. On a warbird of our class, well they (TO ME) just don't look right. And when polishing the wing they'll get in the way. BTAIM, they would surely make a difference in a close 1v1. (But who does things like that? ;-) ). The earliest I remember seeing them was on the B707. They were just ahead of the inboard ailerons on each wing plus just ahead on rudder & elevators on the tail. The 707 had flow separation problem at high mach numbers (> .85 I believe). BTW you could actually see the shock wave on the wind surface if you were seating at window at mid point of the wing. It appeared like a reflection or shadow because the light distorted in the temp change of the shock wave. Anyway was neat to see it. Jim "Pappy" Goolsby In a message dated 1/22/2013 5:01:24 P.M. Eastern Standard Time, mdecanio@mac.com writes: --> Yak-List message posted by: "N642K" Anybody tried these? http://www.microaero.com/index.html Read this topic online here: http://forums.matronics.com/viewtopic.php?p=392894#392894 ________________________________ Message 5 _____________________________________ Time: 05:37:11 PM PST US Subject: Re: Yak-List: Micro Vortex Generators From: "Roger Kemp M.D." On what? Doc Sent from my iPad On Jan 22, 2013, at 3:58 PM, "N642K" wrote: > > Anybody tried these? http://www.microaero.com/index.html > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=392894#392894 > > > > > > > > > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/yak-list Browse Digests http://www.matronics.com/digest/yak-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.