Owls are exceptional predators. In addition to their impressive vision and hearing capabilities, they are also able to fly almost silently. This stealthy flight is thanks to the structure of their wings, which researchers have analyzed and mimicked to develop a prototype coating that they claim could significantly reduce the noise generated by wind turbines, computer fans and airplanes.
Using fine detail microscopy, the researchers from the University of Cambridge in the US and Virginia Tech, Lehigh University and Florida Atlantic University in the US examined owl feathers in fine detail, revealing a downy covering that they say resembles a forest canopy when viewed from above. They also saw a flexible comb of evenly-spaced bristles along the wing's leading edge, while the trailing edge shad a porous and elastic fringe.
"No other bird has this sort of intricate wing structure," said Professor Nigel Peake of Cambridge's Department of Applied Mathematics and Theoretical Physics, who led the research. "Much of the noise caused by a wing – whether it's attached to a bird, a plane or a fan – originates at the trailing edge where the air passing over the wing surface is turbulent. The structure of an owl's wing serves to reduce noise by smoothing the passage of air as it passes over the wing – scattering the sound so their prey can't hear them coming."
Early attempts to replicate this structure included covering a blade with a wedding veil-like material, which, despite the open structure of the material, reduced the roughness of the underlying surface and cut the surface noise by up to 30 dB.
Thank goodness. Alas, too late for those of us who have suffered permanent hearing loss from sitting next to server clusters...
Original Submission
(Score: -1, Troll) by Anonymous Coward on Wednesday June 24 2015, @01:47AM
Sneaking up on children?
(Score: 0) by Anonymous Coward on Wednesday June 24 2015, @02:12AM
Not sure if pedophiles use wind turbines.
(Score: -1, Troll) by Anonymous Coward on Wednesday June 24 2015, @02:16AM
Birds don't prey on children -- there's never been a female teacher who seduced her students.
(Score: 1) by kanweg on Wednesday June 24 2015, @05:31AM
Pro tip: If you say never/always, you're probably wrong.
Google this: Female teachers convicted of sleeping with students
Bert
(Score: 0) by Anonymous Coward on Wednesday June 24 2015, @06:25AM
2 pro-tips for you as well.
1) When you feed a troll, you're probably doing it wrong.
2) Don't let google use you.
(Score: 2) by Tork on Wednesday June 24 2015, @02:33AM
Useful for pedophiles? Sneaking up on children?
Not if you tie a bell around their neck.
🏳️🌈 Proud Ally 🏳️🌈
(Score: 5, Funny) by fleg on Wednesday June 24 2015, @02:33AM
"whoooo-knew? dept."
disgraceful, i hope you're ashamed of yourself.
(Score: 2, Interesting) by Anonymous Coward on Wednesday June 24 2015, @02:43AM
Decades ago, somebody got the bright idea of cutting notches in the trailing edge of fan blades.
Those sawblade-looking things made a few dB less noise.
The patent ran out long ago but these days I rarely see fan blades with this feature.
-- gewg_
(Score: 3, Informative) by c0lo on Wednesday June 24 2015, @03:06AM
Try Noctua [noctua.at] - I'm pretty pleased with their stuff; if lucky, you may find them at local computer parts distributors (I had).
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2, Informative) by anubi on Wednesday June 24 2015, @02:43AM
PBS did a whole show on this very thing. [pbs.org]. Excellent piece of work.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 4, Informative) by gnuman on Wednesday June 24 2015, @02:44AM
There is many different types of wind turbine noise. It's not really the high pitches "swishing" sound that is a problem. Infrasound produced by these structures is most likely the cause of problems in humans and animals.
http://oto2.wustl.edu/cochlea/windmill.html [wustl.edu]
(Score: 2) by MichaelDavidCrawford on Wednesday June 24 2015, @05:32AM
longer slower blades. these are not commonly used. how many base their purchase decisions on fan noise?
i do thats why i used notebooks before most others.
Yes I Have No Bananas. [gofundme.com]
(Score: -1, Troll) by Anonymous Coward on Wednesday June 24 2015, @06:10AM
So first we dig a hole and extract 170 tons of iron. Then dig another hole to mine 170 tons of choke. Then 100+ tons of water (greenhouse gas plus force feedback partner to all computer projections from 1988 to now) to turn those rocks into a turbine.
Install turbine and watch it not produce electricity during cold months and indiscriminately cut birds in half during warm months.
So its awesome to see we learned something from birds.
Now, can we stop building these monstrosities and let the birds live their migratory lives in peace?
(Score: 0) by Anonymous Coward on Wednesday June 24 2015, @06:33AM
The options are not [to build or not to build] a windmill. But [to build a windmill or build a coal plant or nuke plant or solar farm or] ...
(Score: 2, Informative) by Anonymous Coward on Wednesday June 24 2015, @07:52AM
Wind power is way, Way, WAY down on the list of stuff that is dangerous to flying critters.
Chart 1 [wikipedia.org]
Chart 2 [googleusercontent.com] (orig) [thinkprogress.org]
-- gewg_
(Score: 1, Informative) by Anonymous Coward on Wednesday June 24 2015, @12:50PM
Looking at the Wikipedia table, everyone who is against windmills because of the birds should also be violently against buildings. At least those with windows.
Back to the caves!
(Score: 0) by Anonymous Coward on Wednesday June 24 2015, @06:37AM
I suggest you RTFA in this case, you'll find out why this is a big deal in wind turbines and does it cause drag. :)
(Score: 1, Funny) by Anonymous Coward on Wednesday June 24 2015, @02:02PM
w00t!