I thought you guys would find this interesting:

http://www.eurekalert.org/pub_releas...-mhw051104.php

"Mimicking humpback whale flippers may improve airplane wing design"

And, speaking of underwater creatures...
http://www.smartfish.ch/index.cfm/fu...w/path/1-2.htm

Sounds like someone has re-discovered turbulators. Perhaps an enhanced form but turbulators nontheless.

Not really the same thing Bruce. Check out the geometry of the fin/wing. These are bumps on the leading edge... a scalloped leading edge basically. Not the same thing as a traditional turbulator strip.

It depends on your style of turbulators Ken. There's types that go on the leading edge as well. Free flighters have used them in the past but they are not in favour at the moment.

This is not to say that it isn't new or interesting but it sure seems like an enhancement of something we already know about rather than a new principle.

I guess I would think of the tubercle as more of a vortex generator than a turbulator. What is a bit surprising to me is that, from the sound of the article, they reduce drag even at low AoA, when you wouldn't expect separated flow even without them.

banktoturn

If you want to read the paper the link is:

[link=http://www.appliedfluids.com/UUST01.pdf]http://www.appliedfluids.com/UUST01.pdf[/link]

e=mc2

Maybe there is hope for my brick sh--house building standards yet...

From reading the paper I am skeptical. Several years ago, similar (published) claims were made about induced drag savings from highly sheared wing tips. It turned out that the drag savings were an artifact of the computational method (predicted drag became very sensistive to panel spacing as the leading edge sweep increased). The paper did not go into detail as to whether the researchers investigated different panel geometries or densities in this case.

The article refers to wind tunnel testing. I think the Physics of Fluids paper will be enlightening. It will be interesting to see how this work holds up in the stark light of peer review.

As for tubercles effectiveness, wind tunnel test run on a smooth fin and a fin with tubercles, proved that the computer model was born out. So the resullts being reported are not based solely on computer models and likely to have the same effect upon fu ll scale aircraft wings, providing the air speed is relatively low.

Bryan Swinney
Native Texican & US Westerner
Houston, Texas, USAa

Man discovers nature

Can anyone tell me what is going on in this forum? Is anyone interested in getting news about the latest technologies?
==============================
rene

Nourish your body with Naturally Nova Scotia's certified organic whole food supplements. Made with real food as Mother Nature intended.

[link=http://www.naturallynovascotia.com/]Organic Whole Food Nourishment[/link]

Rene, you'll need to be a little more specific. Are you asking about any further developments in making wings look like whale flippers or are you concerned that we are ignoring the lastest tests in our desire to design a flying whale?

It's always quite puzzling when someone brings back really old threads like this without making it clear just exactly what and why they did so.

I'm guessing that someone saw the "Organic" in the subject line, wanted a hook to hang Organic Whole Food on, and brought back the thread.