A very interesting article about the interaction of sound and fire (candle flame). A video of the experiment can be found here.
Mythbusters also seem to have explored the same: http://mythbustersresults.com/episode76
From the article:
"In 2004 Dmitriy Plaks and several of his fellow students at the University of West Georgia tested whether sound waves can douse fires in hopes of using sound to extinguish flames in a spacecraft. They placed a candle in a large topless chamber with three bass speakers attached to the walls. The candle was lit and the Canadian rock band Nickelback's "How you remind me" was pumped through the subwoofers. Within roughly 10 seconds, once the song hit a low note, the flame was out, according to results published in 2005 in The Journal of the Acoustical Society of America.
"We don't know exactly what's going on," Plaks says, now a student at the Georgia Institute of Technology.
Physicist James Espinosa at Rhodes College in Memphis, Tenn., a former advisor to the student team, notes that the candle wasn't running out of oxygen to fuel the flame because the chamber was large and open to the air. He also doesn't believe that wind—which would actually displace the warm air around the candle with cooler air—had put out the fire, although only high-resolution thermal images would have been able to verify that.
There is another indication that the fire hadn't been extinguished by wind: frequency (the time it takes for succeeding peaks of a sound wave to pass a fixed point). "There's some special frequency at which a candle flame extinguishes," Espinosa notes. The students tested a range of frequencies from five to several hundred hertz. They found that the effective range was between 40 and 50 hertz, within the range of human hearing."
My guess that it has to do something with resonance of the sound waves. Maybe we should equip our firetrucks with large speakers blaring music or sound at different frequencies. This should speed up the process of containing fires.
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