The U.S. defense agency’s “Instant Fire Suppression” program could have life-saving benefits, especially in enclosed spaces such as aircraft cockpits and ship holds where fires can be devastating.
n DARPA’s demonstration of the ‘wall-of-sound’ system, the team arranged two speakers either side of a liquid fuel flame. By activating the acoustic field and amping up the air velocity, the team used the sound system to thin the area of the flame where combustion occurs, known as the flame boundary. This makes the flame easier to extinguish, and the acoustics also disturb the pool of fuel to create higher fuel vaporization – this makes the flame less concentrated and easier to extinguish.
“We have shown that the physics of combustion still have surprises in store for us,” said DARPA manager Matthew Goodman in a statement. “Perhaps these results will spur new ideas and applications in combustion research.” DARPA’s project was started in 2008 in order to research the viability of electromagnetism and sonic waves in fire extinguishing. Amazingly, despite extensive research in this area, there have been no new methods for extinguishing and/or manipulating fire in almost 50 years.
While DARPA’s demonstration took place on a 10 cm square area, the team plans to implement the system on a larger scale for naval, air force and possibly even space vehicles.