Traditionally, water has been the go-to source for fighting fires. Apparently low-frequency sound waves do the trick as well.
Two electrical and computer engineering students at
George Mason University
have developed an extinguisher that uses low-frequency sound waves to eliminate fire. At first, the duo thought high frequencies could douse a blaze. “But it’s low-frequency sounds—like the thump-thump bass in hip-hop that works,” Viet Tran, one half of the engineering team, told the university.
How the low-frequency extinguisher works
So how does their extinguisher function? Sound waves double as pressure waves. They can impact objects around them (including ones that are burning). In the scenario of a fire, sound waves serve to separate the burning material and the oxygen – which fuels fire – around it, thus eliminating the flame.
Scientists have known for a few years now that sound waves can affect fire. In fact, the Defense Advanced Research Agency (DARPA) developed a system back in 2012 that utilized sound to put out flames. However, this marks the first time engineers have created an actual extinguisher using sound.
Creating the prototype
The two-person team, which also includes senior engineering student Seth Robertson, developed the 20-pound prototype with just $600. Their device, which also eliminates collateral damage caused by sprinkler systems, does not use any toxic chemicals. The extinguisher is comprised of a cardboard-tube collimator (which helps focus the sound waves), a power source and an amplifier. Tran and Robertson went through multiple trials before settling on sound waves in the 30 to 60 Hertz range.
The engineers hold a preliminary patent application for their extinguisher. However, they still have a lot of work ahead of them before the device can hit the market. It has only been used on small fires thus far, so the team needs to figure out whether the extinguisher will be useful for large, real-life flames. Additionally, the device does not include a coolant, which could result in the resurgence of the fire once the extinguisher is turned off.
But there’s no question the potential is there. According to team, the device could potentially come in handy to combat fires in large urban centers and to confront forest fires – particularly if used in conjunction with a drone.