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Owl wing design reduces aircraft, wind turbine noise pollution
Phys Org ^ | 18 January 2022 | American Institute of Physics

Posted on 01/18/2022 8:35:41 AM PST by Scarlett156

Trailing-edge noise is the dominant source of sound from aeronautical and turbine engines like those in airplanes, drones, and wind turbines. Suppressing this noise pollution is a major environmental goal for some urban areas.

In Physics of Fluids, researchers from Xi'an Jiaotong University used the characteristics of owl wings to inform airfoil design and significantly reduce the trailing-edge noise.

"Nocturnal owls produce about 18 decibels less noise than other birds at similar flight speeds due to their unique wing configuration," said author Xiaomin Liu. "Moreover, when the owl catches prey, the shape of the wings is also constantly changing, so the study of the wing edge configuration during owl flight is of great significance."

Trailing-edge noise is generated when airflow passes along the back of an airfoil.

(Excerpt) Read more at phys.org ...


TOPICS: Miscellaneous; Pets/Animals; Science
KEYWORDS: aeronautics; animals; birds; fringe; noise; owls; science
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To: Scarlett156

“Those giant muscular feet are the best landing gear. “

But aren’t they going at about zero velocity when those claws touch their landing point?

Do you know why an owl can turn its head almost all the way around? It’s because its eyeballs are so big that it can’t turn them independently of its head.


21 posted on 01/18/2022 9:58:32 AM PST by cymbeline
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To: Scarlett156

Soon quiet helicopters.


22 posted on 01/18/2022 10:00:34 AM PST by Agatsu77
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To: Scarlett156

Wind turbine noise. Oops. But I thought wind power had no downside...


23 posted on 01/18/2022 10:06:03 AM PST by Freedom_Is_Not_Free (America -- July 4, 1776 to November 3, 2020 -- R.I.P.)
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To: Seruzawa

Last week while putting out my bird feeders and walking through the yard I saw a large circle of blue jay feathers (about two feet in diameter). I thought it must have been one of our ever present hawks that caught its dinner but it could have been one of our barred owls that live in our neighborhood. That bluejay did not have a good end.


24 posted on 01/18/2022 10:43:28 AM PST by punknpuss
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To: Scarlett156

It appears every time I read about a new breakthrough, it’s coming out of China.


25 posted on 01/18/2022 10:44:59 AM PST by Lazamataz (He who does, does not talk. He who talks, does not do.)
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To: Hot Tabasco

Blue Jays are asshole birds.


26 posted on 01/18/2022 10:47:27 AM PST by Lazamataz (He who does, does not talk. He who talks, does not do.)
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To: Scarlett156
IIRC, the Horten brothers put a lot of thought into wingtip and trailing-edge design for their flying wing aircraft.


27 posted on 01/18/2022 10:48:26 AM PST by PLMerite ("They say that we were Cold Warriors. Yes, and a bloody good show, too." - Robert Conquest )
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To: Lazamataz

Not to mention their baseball team, they ain’t even American.


28 posted on 01/18/2022 10:51:57 AM PST by dfwgator (Endut! Hoch Hech!)
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To: TexasGator

Hey TG
Survival of the pffttt.
Your theory lacks evidence. But it has a large imagination.


29 posted on 01/18/2022 11:07:11 AM PST by Honest Nigerian
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To: Scarlett156

Fig 3. Schematic of geometric models of the (a) owl-based airfoil, (b) oblique-arc trailing-edge serrations, and (c) conventional trailing-edge serrations.

30 posted on 01/18/2022 11:14:47 AM PST by Alas Babylon! (Rush, we're missing your take on all of this!)
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To: Honest Nigerian

“Your theory lacks evidence.”

Your theory?


31 posted on 01/18/2022 11:18:53 AM PST by TexasGator (UF)
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To: Flick Lives
One can see why many American Indian tribes consider owls harbingers of death.

Owls are bad omens. I had an owl fly into my house window (it left a dust impression on the window). A week later my dog died.

32 posted on 01/18/2022 11:20:08 AM PST by mjp (pro-freedom & pro-wealth $)
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Comment #33 Removed by Moderator

To: Big Red Badger

My torment always entertains people. The upside is that I’m me.


34 posted on 01/18/2022 11:36:57 AM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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To: Freedom_Is_Not_Free

There’s always a downside to wind turbine power. Owls and many other birds are unnecessarily slaughtered. Personally I’m not in favor of turbines. Just passing on an article I read.


35 posted on 01/18/2022 11:53:49 AM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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To: Scarlett156

boundary layer shedding? or not fast enough


36 posted on 01/18/2022 11:59:42 AM PST by Chode (there is no fall back position, there's no rally point, there is no LZ... we're on our own. #FJB)
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To: PLMerite

Wow, cool!


37 posted on 01/18/2022 12:29:34 PM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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To: cymbeline

Thank you for posting!


38 posted on 01/18/2022 12:30:09 PM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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To: GOYAKLA

Poor Brandon! :(


39 posted on 01/18/2022 12:31:10 PM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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To: ping jockey

Maybe the turkeys and owls are acting in partnership. (Turkey hunting takes a lot of skill btw! You can see 20 turkeys and then really... slowly... get your gun out and by the time it’s cocked, there are no turkeys!)


40 posted on 01/18/2022 12:33:41 PM PST by Scarlett156 (I'm really starting to hate all comedy. Comedians are the worst people. Prove me wrong. You can't.)
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