Owl Wings Are Helping Silence Airplanes, Fans, And Wind Turbines
Source
Quote:
What I wonder is if adding a fine mesh coating that reduces trailing-edge drag would add enough skin friction to offset the reduction in turbulence. Either way though, silence is something to be valued. |
Interesting how how a lot of designs they look to nature and copy it.
|
Nature has found its ways already via evolution. Almost all we know now comes from nature. But the details from alot of stuff is getting griped bij people now.
|
Quote:
|
Small-'C' creator, I see. I lean more toward the Anthropic Principle, Weak or Strong.
This is a good example of Biomimetics, and a different approach to semi-permeable surfaces generally. Quote:
Edit: Then there is this from The Register: Engineers 3D-print ROBOT SEAHORSE, then BATTER it with rubber mallets It being El Reg, you'll notice the title in the actual URL is "/seahorse_tails_robot_tales_were_all_going_to_die/". |
I'm sceptical that there'll be any perceivable decrease in airplace noise (both interior and exterior) but the Wind Turbines is certainly an interesting application and a turbine noise is often used by anti-wind turbine groups.
Quote:
It's a funny thing, we've known for years that animals are capable of some amazing things that we would do well to replicate, but the technology and funding to really look into it has only recently become available in some instances. |
Quote:
http://ecomodder.com/forum/member-fr...29-0-large.jpg The real fun is when you take what Bucky Fuller called 'generalizable principles' from nature and apply them to things nature never addressed. Beetle wings to LCD screens kind of stuff. Or Bucky-tubes/balls and graphene. |
trailing edge
Automotive drag is associated with separation-induced pressure drag.
If you have a streamlined shape,the trailing edges will also be streamlined and the car will only suffer from surface friction drag which cannot be removed. Any 'feather down' attached to the aft-body would already be embedded within the thickened turbulent boundary layer and only add turbulence and drag. As to noise,most of that is coming from the tires. Owls fly at very low flight velocity,below critical Reynolds number.They're in a laminar boundary layer up to maximum cross-section and 1st minimum pressure on the wings.It's nothing like an automobile. Their down is attached to nerve endings.As their angle of attack approaches stall,their central nervous system will cause the bird to morph it's wings such to defeat the stall,within a closed-loop feedback system.Again,it's nothing like an automobile. Owl technology was very important during the Vietnam War,where the USA had aircraft operating overhead at very low altitude which could not be heard from the ground.A large suite of features combined to allow the acoustic stealth performance.NASA has studied Raptor/Owl acoustics extensively. |
Quote:
Now we have Black Helicopters. |
Google for Lockheed YO-3 aircraft, essentially a Sweitzer sailplane with 5 or 6 bladed slow moving propeller, engine, and a long muffler. It was a dog to fly, being under powered and over weight, but never took a round of enemy fire, since it pretty much flew at night and Charlie never heard it coming. There is an alumni website for YO-3 guys.
The FBI had a couple of these Army surplus planes at Pt. Mugu in the late '70s. Used them in the Patty Hearst kidnapping, etc. I talked to the crew chief, who told me that if one flew over in the dark about 50 feet overhead, all you'd hear was about the same as a flock of birds at that height, like ducks or geese, not honking. NASA has or had one of the final versions, 3 paddle blade wood prop, to carry microphones to test helicopter noise, flown in close formation. Based at an old (Moffat?) Navy airfield at the south end of the San Francisco Bay. |
All times are GMT -4. The time now is 08:27 PM. |
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com