DARPA fighting fire with… sound?

20 Jul

Here’s one of the coolest 10-second YouTube clips you’re likely to see. It’s the researchers at the Pentagon’s Defense Advanced Research Projects Agency putting out a fire with sound:

How did they do it? Well, as the DARPA website explains, traditional approaches to extinguishing have always focused on the chemical side of fire. However, researchers have long theorized that fires could also be put out by bringing physics into the equation. In the video test, two dynamics were at play:

First, the acoustic field increases the air velocity. As the velocity goes up, the flame boundary layer, where combustion occurs, thins, making it easier to disrupt the flame. Second, by disturbing the pool surface, the acoustic field 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.

DARPA isn’t yet sure how to scale this sort of thing down to the point where it’s practical and usable. But, with the rate at which technology improves, perhaps the inevitable iPhone 10 will feature a fire-extinguishing app.


Posted by on July 20, 2012 in DARPA


3 responses to “DARPA fighting fire with… sound?

  1. Daniel Friesen

    July 20, 2012 at 4:03 am

    Apps wouldn’t interest me that would be pointless. What would really be interesting would be if this scaled up so that instead of apartments being fitted simply with sprinklers there would be a large array of compact speakers which shortly after a hazardous fire is detected are automatically used to put it out. This would be done on pure-electricity and it would not cause water damage meaning that this can be applied much quicker in situations where we’d still be wondering if it’s finally crossed the threshold that we should turn on a sprinkler system. Most dangerous fires would be put out before they damaged any property.

    And if you equipped firefighters with machinery like this… — heck, you could probably robotize this technology — with very powerful sound systems you could probably have a stronger effect on the fire early on. You can blast more sound than you can blast water. The sound will bounce and affect areas of the building that the water could not reach. And to top it off if could probably send a team of firefighters into the blaze with this kind of machinery radiating around the firefighters. It would not put out the whole fire but it would severely weaken the fire in the immediate vicinity essentially creating a portable safe bubble. This could allow a team of firefighters to get deep into a normally lethal area and rescue anyone remaining in the building.

  2. Daniel Friesen

    July 20, 2012 at 4:28 am

    iPhone 10… seriously?
    The iPhone was released 2007, the 3G in 2008, the 3GS in 2009, the 4 in 2010, and the 4S in 2011. Making Apple’s current pattern a fairly consistent pattern. One where we’re due for an iPhone 5 this year. And apple continues on a pattern where the next year they release an S version, then the year after that they release the next iPhone.
    Under this pattern the mythical iPhone 10 would be released in the year 2022. That’s 10 years!

    10 years ago this is where we were:

    From this, I would say that an iPhone 10 will never exist. Tech innovates fast. Computational power at an exponential rate. In 10 years the name “iPhone” will be regarded as a name tied to dead technology and laughed at if someone tried to release a produce with that name. The smartphone as it is today will be a dead technology replaced by something new and even more innovative than what we know now.

  3. Tracey

    July 20, 2012 at 8:42 am

    Woah there Daniel. You need to think a little less literally and get a sense of humour.

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