Darpa is showing off a new system that can put out flames using only sound. It’s part of the U.S. defense agency’s “Instant Fire Suppression” program.
At the Defense Advanced Research Projects Agency (Darpa) have published the video alongside details of how the technique was achieved in their labs back in December 2011.
The team arranged two speakers either side of a liquid fuel flame to demonstrate how fire can be controlled by amping up an acoustic field. The sound increases air velocity, which then thins the area of the flame where combustion occurs, known as the flame boundary. Once the boundary area is thinned, the flame is easier to extinguish. At the same time, the acoustics are disturbing the pool of fuel and creating higher fuel vaporisation — this widens the flame, thinning it out so it is less concentrated and cool enough to extinguish.
Even better, the sound does not even need to be offensively loud to achieve any of this.
keyboard shortcuts: V vote up article J next comment K previous comment