DARPA puts out fires –with sound!

Instead of a fire hose connected to a hydrant, firefighters in the future may be using big loudspeakers to put out fires, a tech site reported Tuesday.

The US Defense Advanced Research Projects Agency (DARPA) unveiled last week a new firefighting technique that aims low-frequency sounds to put out a fire.

"Billy Joel didn’t start the fire! But, if he played at the right frequency, he could put it out!" it said in a post on its Google+ account.

A YouTube video demonstrating the technique is embedded in the post:

On the other hand, tech site CNET quoted a DARPA statement as saying the sound "leads to higher fuel vaporization, which widens the flame, but also drops the overall flame temperature."

"Combustion is disrupted as the same amount of heat is spread over a larger area," it added.

The CNET report said the resulting acoustics increase air velocity, "making it easier to alter the origin of the fire's combustion, also known as the flame boundary layer." — TJD, GMA News