Hell Man
12th Jun 2010, 14:49
Not the be left behind by European advances in blade noise reduction research NASA, finally, embarks on a campaign to make 'whisper mode' a reality!
NASA Pursues ‘Whisper Mode’ In World’s Biggest Wind Tunnel
By Jason Paur
http://www.wired.com/images_blogs/autopia/2010/06/461657main_ACD10-0087-004_full-660x471.jpg
As more and more helicopters are used for everything from medical transportation to news gathering, more and more people on the ground are complaining about the noise. NASA recently spent several months researching new design ideas to make helicopters quieter and more efficient. The work could not only make things quieter on the ground, but could lead to faster helicopters that are able to carry a bigger payload.
“NASA hopes to make those new designs quieter, faster, more fuel efficient, and capable of carrying more people and cargo,” said Tom Norman, the researcher for the project test team.
The research was performed at the world’s largest wind tunnel located at the Ames Research Center in Moffett Field, California. There researchers used a rotor from a Sikorsky UH-60 Blackhawk helicopter mounted on a fuselage used only for the research. The goal was to study the interaction between the rotor blades and the air.
Pilots often like to joke that helicopters don’t fly, they simply beat the air into submission. But the truth is most of the noise and vibration is due to the main and tail rotor blades interaction with the air. The NASA researchers used a technique known as particle image velocimetry to study the airflow over the rotor blades. The technique uses laser light to measure the airflow without having to touch, and therefore interfere with the rotor blades. NASA says the research conducted with the massive Blackhawk rotor blades was the largest ever using this technique.
High speed cameras were also used to watch and measure how the blades flex and bend during flight. A helicopters main rotor blades are constantly twisting and turning during flight. A blade moving forward relative to the direction of flight has very different loads compared to the retreating blade. The high speed cameras along with sensors were used to measure the rotor lift.
Helicopter noise is a major factor affecting operations around the world. Helicopter makers including Eurocopter, Bell and Sikorsky are investing in quiet technologies that will allow expanded helicopter use in both combat and civilian markets.
NASA Pursues ‘Whisper Mode’ In World’s Biggest Wind Tunnel | Autopia | Wired.com (http://www.wired.com/autopia/2010/06/nasa-whisper-mode/)
NASA Pursues ‘Whisper Mode’ In World’s Biggest Wind Tunnel
By Jason Paur
http://www.wired.com/images_blogs/autopia/2010/06/461657main_ACD10-0087-004_full-660x471.jpg
As more and more helicopters are used for everything from medical transportation to news gathering, more and more people on the ground are complaining about the noise. NASA recently spent several months researching new design ideas to make helicopters quieter and more efficient. The work could not only make things quieter on the ground, but could lead to faster helicopters that are able to carry a bigger payload.
“NASA hopes to make those new designs quieter, faster, more fuel efficient, and capable of carrying more people and cargo,” said Tom Norman, the researcher for the project test team.
The research was performed at the world’s largest wind tunnel located at the Ames Research Center in Moffett Field, California. There researchers used a rotor from a Sikorsky UH-60 Blackhawk helicopter mounted on a fuselage used only for the research. The goal was to study the interaction between the rotor blades and the air.
Pilots often like to joke that helicopters don’t fly, they simply beat the air into submission. But the truth is most of the noise and vibration is due to the main and tail rotor blades interaction with the air. The NASA researchers used a technique known as particle image velocimetry to study the airflow over the rotor blades. The technique uses laser light to measure the airflow without having to touch, and therefore interfere with the rotor blades. NASA says the research conducted with the massive Blackhawk rotor blades was the largest ever using this technique.
High speed cameras were also used to watch and measure how the blades flex and bend during flight. A helicopters main rotor blades are constantly twisting and turning during flight. A blade moving forward relative to the direction of flight has very different loads compared to the retreating blade. The high speed cameras along with sensors were used to measure the rotor lift.
Helicopter noise is a major factor affecting operations around the world. Helicopter makers including Eurocopter, Bell and Sikorsky are investing in quiet technologies that will allow expanded helicopter use in both combat and civilian markets.
NASA Pursues ‘Whisper Mode’ In World’s Biggest Wind Tunnel | Autopia | Wired.com (http://www.wired.com/autopia/2010/06/nasa-whisper-mode/)