Sounding Off
A new technique for harnessing the power of sound waves will be unveiled today at the National Meeting of the Acoustical Society of America in San Diego.
MacroSonix, a start-up firm from Richmond, Va., will describe how it used resonant macro-sonic synthesis, or RMS, to create a customized sound wave inside a closed container and produced energy densities more than 1,600 times greater than those of any previous efforts.
For starters, MacroSonix is using the technology to make an energy-efficient compressor, and a Fortune 500 company--which MacroSonix declines to name--is incorporating it into new refrigeration and cooling devices.
Most acousticians had abandoned the idea of milking energy from sound waves because when the waves hit the shock barrier, they dissipate their energy as heat.
But 10 years ago, physicist Tim Lucas started testing sound waves inside closed chambers and found that the shape of the sound wave could be controlled by adjusting the shape of its container.
“Then you can synthesize a wave shape which is not a shock wave, and now you’ve gotten around the shock barrier and you can put as much energy, pressure and power in that wave as you want,” Lucas said.
Today, RMS can produce hundreds or even thousands of pounds per square inch of pressure, he said. The pressure forces the torpedo-shaped chamber to vibrate, and MacroSonix uses a motor technology to convert those vibrations into electric power.
“In the acoustics community, no one has achieved such high-pressure oscillation amplitudes before. This is a technology breakthrough,” said Greg Swift, a technical staff member in the condensed matter and thermal physics group at Los Alamos National Laboratory in New Mexico.
Lucas said the technology is well-suited for making compressors because there are no moving parts that require lubricants or chlorofluorocarbons and because the whole contraption is less likely to break.
Because the compressor is so clean, Lucas expects to find customers from the semiconductor, pharmaceutical and chemical manufacturing industries. The first licensing deal netted MacroSonix $3.5 million, according to company spokesman Mike Mulvilhill, and Lucas expects to sign two or three more deals in the next year.
“They’ve got a very novel device that people will find applications for,” said Mark Hamilton, a professor of mechanical engineering at the University of Texas at Austin, who has sent four former students to work at MacroSonix.
Lucas said MacroSonix has raised about $10 million from venture capitalists and investment banks since its founding in 1990. The company now has 20 employees--including seven researchers with doctorates--and has received 10 patents so far.
