Technology & Science

Ottawa invention aims to quiet helicopters, wind turbines

A Carleton University graduate student is trying to launch a business based on a device that could make wind turbines quiet enough to install closer to people's homes and make loud, rattling helicopter rides a thing of the past.
Kostyantyn Khomutov, 24, is working on his master's degree in mechanical and aerospace engineering at Carleton University. ((Carleton University))
A Carleton University graduate student is trying to launch a business based on a device that could make wind turbines quiet enough to install closer to people's homes and make loud, rattling helicopter rides a thing of the past.

"Right now, whenever you're in the helicopter, in the older ones, especially, you're feeling lots of shaking," said Kostyantyn Khomutov Monday.

He and his team will be pitching their invention, named Active Pitch Link, at the finals of the Technology Venture Challenge, an annual business competition for post-secondary students in the Ottawa area, on Tuesday.

"What we're aiming for is to have a jet-smooth ride," Khomutov said.

The device could also be applied to wind turbines. The noise and vibrations those turbines currently generate have been blamed by some people who live near them for sleep disruptions and other health problems.

The vibrations in both helicopter and wind turbine rotors don't just affect humans but also components of the machines themselves, Khomutov said. Reducing the vibrations could boost the service life and cut maintenance costs for those components, he added.

Khomutov's team is one of three finalists at the Ottawa competition. The other finalists are:

  • Muhammad Arsalan and Atif Shamim from Carleton University, who have developed a device that extends the battery life of portable gadgets such as the iPhone and BlackBerry by eliminating wires used to connect the electronic circuits with the antenna.
  • Dan Dicaire from the University of Ottawa, who has developed a hybrid material that can store thermal energy from the sun for long periods of time and can be used with solar panels to heat homes.

The winners will get $10,000, and the runners-up will receive $5,000 each.

$100,000 prize from Ontario government

The Active Pitch Link is a device that constantly adjusts the angle and stiffness of individual rotor blades. ((Courtesy of Kostyantyn Khomutov))
In the fall, 24-year-old Khomoutov, who is working on his master's degree in aerospace and mechanical engineering, won a $100,000 fellowship from the provincial government's Ontario Centres of Excellence. The money is intended to cover his salary as chief technology officer and interim CEO of Smart Rotor Systems, the company he co-founded to commercialize the vibration-damping device.

The Active Pitch Link was developed over roughly five years by a team of Carleton researchers overseen by professors and fellow Smart Rotor Systems co-founders Daniel Feszty and Fred Nitzsche. It is based on research that has been ongoing at Carleton for more than 15 years, Khomoutov said.

The device is installed at the base of the rotor blades and works by constantly adjusting the angle and stiffness of each blade to deal with aerodynamic effects that generate the noise and vibrations as a rotor turns.

Those aerodynamic effects result from the different conditions experienced by each blade as it passes through different positions in its path, Khomutov said.

"On one side, it's experiencing a loss of force that is lifting it up," he said. "On the other end, it basically goes so fast that it creates … air flow barriers." 

Each blade normally has airflow coming off it that gets caged by the blade following after it, creating additional noise, said Khomutov.

So far, tests of individual components of the Active Pitch Link have been successful, and computer simulations of the entire device suggest that it will drastically reduce noise and vibrations.

Testing to take place in next few years

However, Khomutov said the team wants to complete actual tests of the entire device before commenting on how much it could reduce rotor noise.

Tests of the entire device on a rotating frame are expected to be complete within a year. That will be followed by wind tunnel and flight tests before it can be certified for use on commercial aircraft, about four years from now, Khomutov estimates.

A spokeswoman for the Canadian Wind Energy Association said most of the noise from wind turbines is caused by the aerodynamic relationship between blades and the tower on which they are mounted. However, the association was not available to comment further on Monday.

Khomutov was born in Ukraine and completed high school in Ottawa after moving there at age 15. During his undergraduate studies in aerospace engineering at Carleton University, he started and ran a small business that exported high-end North American cars to Europe.

Khumotov started working with Feszty and Nitzsche three years ago as a summer student and said his current work involves integrating all the sub-components of the Active Pitch Link, developed by various researchers in the team, into a single device. He is also dealing with the intellectual property aspects of the operation.

Research groups at the University of Michigan, Boeing, NASA and other companies and institutions around the world have been trying to develop rotor vibration-reduction systems for a long time.

NASA announced in February that tests showed shape-changing, adjustable flaps on the trailing edge of the rotor blades that it had developed can cut the amount of noise the rotor produces by 50 per cent in a wind tunnel.

A German company named ContiTech has created a system that produces counter-vibrations to oppose the vibrations created by wind turbine rotors.

Khumotov said because such systems don't actually eliminate the vibrations at their source, they still affect the components, reducing their service life.