Did you know you can put out a fire with a low-rumbling bass frequency generator?
No! Neither did I!
Over the two last-year engineering majors at George Mason University, in Fairfax, Virginia, appear to have invented a way to use sound waves to put out fires. It started as an idea for a research project, and after a year of trial and error and spending about $600 of their own money, they have built a somewhat portable sound generator, amplifier, power source and focusing tube that would seem to have great potential in attacking fires in a variety of situations.
Robertson, 23, and Tran, 28, applied for a provisional patent at the end of November, which gives them a year to do further testing on other flammable chemicals – so far they have put out only fires started with rubbing alcohol – and to continue to refine their device. Although they originally conceived of the device as a way to put out kitchen fires and, perhaps, fires in spacecraft, a local fire department already has asked them to test their bass waves on a structure fire; they think the concept could replace the toxic chemicals involved in fire extinguishers.
"There’s nothing on the market that works, so we thought we could be the ones to make it happen."
Robertson of Newport News, Virginia, and Tran of Arlington, Virginia, are electrical and computer engineering majors, and the idea for their project came about only because they didn’t like the ideas that their professors had proposed. They had seen research on how sound waves could disrupt flames, “but there’s nothing on the market that works”, Robertson said. “So we thought we could be the ones to make it happen. And that’s the inspiration for the project.”
As with all great scientific inspiration, there were plenty of naysayers, the pair said. They are electrical engineers, not chemical, and were told, “You guys don’t know what you’re talking about,” Tran said. A number of faculty members declined to serve as advisers on the project, but Professor Brian Mark agreed to oversee it and not fail them if the whole thing flopped, Tran said.
But how does it work? The basic concept, Tran said, is that sound waves are also “pressure waves, and they displace some of the oxygen” as they travel through the air. Oxygen, we all recall from high school chemistry, fuels fire. At a certain frequency, the sound waves “separate the oxygen from the fuel. The pressure wave is going back and forth, and that agitates where the air is. That specific space is enough to keep the fire from reigniting.”
Found on the Guardian - http://www.theguardian.com/science/2015/mar/27/students-fire-extinguisher-sound-waves