Nav: Home

Owls' wings could hold the key to beating wind turbine noise

July 03, 2017

Owls' wings could hold the key to beating wind turbine noise

A new study has revealed how inspiration from owls' wings could allow aircraft and wind turbines to become quieter.

Researchers from Japan and China studied the serrations in the leading edge of owls' wings, gaining new insight into how they work to make the birds' flight silent.

Their results, published today in the journal Bioinspiration and Biomimetics, point towards potential mechanisms for noise suppression in wind turbines, aircraft, multi-rotor drones and other machines.

Lead author Professor Hao Liu, from Chiba University, Japan, said: "Owls are known for silent flight, owing to their unique wing features, which are normally characterised by leading-edge serrations, trailing-edge fringes and velvet-like surfaces.

"We wanted to understand how these features affect aerodynamic force production and noise reduction, and whether they could be applied elsewhere."

The researchers analysed owl-inspired feather wing models with and without leading edge serrations, by combining large-eddy simulations - a mathematical model for turbulence used in computational fluid dynamics to simulate air flows - and Particle-Image Velocimetry (PIV) and force measurements in a low-speed wind tunnel.

They discovered leading-edge serrations can passively control the transition between laminar, or streamline air flow, and turbulent air flow over the upper wing surface, at angles of attack (AoA) between zero and 20 degrees. This means they play a crucial role in aerodynamic force and sound production.

Professor Liu said: "We found, however, that a trade-off exists between force production and sound suppression. Serrated leading-edges reduce aerodynamic performance at lower AoAs than 15° compared to clean leading-edges, but can achieve noise reduction and aerodynamic performance at AoAs above 15°, which owl wings often reach in flight.

"These owl-inspired leading edge serrations, if applied to wind turbine blades, aircraft wings or drone rotors, could provide a useful biomimetic design for flow control and noise reduction.

"At a time when issues of noise are one of the main barriers to the building of wind turbines, for example, a method for reducing the noise they generate is most welcome."
-end-


IOP Publishing

Related Wind Turbines Articles:

Safe flight: New method detects onset of destructive oscillations in aircraft turbines
''Flutter'' is a complex oscillatory phenomenon that can destroy aircraft turbine blades and has historically been the cause of several plane accidents.
New system uses wind turbines to defend the national grid from power cuts
A 'smart' system that controls the storage and release of energy from wind turbines will reduce the risk of power cuts and support the increase of wind energy use world-wide, say researchers at the University of Birmingham.
Wind beneath their wings: Albatrosses fine-tuned to wind conditions
A new study of albatrosses has found that wind plays a bigger role in their decision to take flight than previously thought, and due to their differences in body size, males and females differ in their response to wind.
Designing lightweight glass for efficient cars, wind turbines
A new machine-learning algorithm for exploring lightweight, very stiff glass compositions can help design next-gen materials for more efficient vehicles and wind turbines.
Quadrupling turbines, US can meet 2030 wind-energy goals
The United States could generate 20% of its electricity from wind within 10 years, without requiring any additional land, according to Cornell University research published in Nature Scientific Reports.
Supporting structures of wind turbines contribute to wind farm blockage effect
Much about the aerodynamic effects of larger wind farms remains poorly understood.
Wind and water
Damaging rains from hurricanes can be more intense after winds begin to subside, say UC Santa Barbara scientists.
Silverswords may be gone with the wind
In a new study in the Ecological Society of America's journal Ecological Monographs, researchers seek to understand recent population declines of Haleakalā silverswords and identify conservation strategies for the future.
Computer models show clear advantages in new types of wind turbines
Researchers from Aarhus University and Durham University have modelled the fluid dynamics of multi-rotor wind turbines via high-resolution numerical simulations.
(Not only) the wind shows the way
When the South African dung beetle rolls its dung ball through the savannah, it must know the way as precisely as possible.
More Wind Turbines News and Wind Turbines Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.