They are also developing a computer model to predict the noise output from wind farms so they can accurately and quickly assess the effectiveness of potential noise-reducing designs and control methods.
Research leader Dr Con Doolan, of the University’s School of Mechanical Engineering, said the noise generated from wind turbines is ‘trailing edge or airfoil noise’, the same sort of noise generated at the edge of aircraft wings.
“We know generally what causes that noise – as the turbulent air flows over the sharp edge of the blade it radiates sound much more efficiently, so the noise can be heard at some distance,” said Dr Doolan.
“What we don’t yet understand, however, is exactly how that turbulence and blade edge, or boundary layer, interact and how that makes the noise louder.
“If we can understand this fundamental science, we can then look at ways of controlling the noise, through changing the shape of the rotor blades or using active control devices at the blade edges to disrupt the pattern of turbulence and so reduce the noise.”
Dr Doolan said further complicating factors came from the effects of multiple wind turbines together and the way the noise increases and decreases as the blades rotate – the blade ‘swish’. The model they are developing will look at the noise from the whole wind turbine and how multiple numbers of wind turbines together, as in a wind farm, generate noise.
“Wind turbine noise is very directional. Someone living at the base might not have a problem but two kilometres away, it might be keeping them awake at night,” he said.
“Likewise this broadband ‘hissing’ noise modulates up and down as the blades rotate and we think that’s what makes it so annoying,” he said.
“Wind turbine noise is controversial but there’s no doubt that there is noise and that it seems to be more annoying than other types of noise at the same level. Finding ways of controlling and reducing this noise will help us make the most of this very effective means of generating large amounts of electricity with next to zero carbon emissions.”Dr Con Doolan
Dr Con Doolan | Newswise Science News
Electrical fields drive nano-machines a 100,000 times faster than previous methods
19.01.2018 | Technische Universität München
ISFH-CalTeC is “designated test centre” for the confirmation of solar cell world records
16.01.2018 | Institut für Solarenergieforschung GmbH
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy