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Refrigerators To Cool With Sound (Cool!)

T-Kir writes "A very interesting report from the BBC where researchers at Penn State University are developing a prototype fridge that cools using metal plates and sound waves. If successful, this technology would help remove the dependance on gases that contribute to global warming. Talk about Cool!"

18 of 436 comments (clear)

  1. But... by Telastyn · · Score: 5, Funny

    Reduce the gases that contribute to global warming, but contribute to noises that drive Fido mad...

    </senseless humour>

    1. Re:But... by homer_ca · · Score: 5, Interesting

      I'd worry about my ears more than Fido's. The article doesn't say the frequencies are ultrasonic, so it's possible human ears will need protection too. I can't imagine how much sound insulation you'd need to hold in 173dB. What happens if the chiller doesn't cut off when you open the fridge door? I'm picturing the last scene of Raiders of the Lost Ark where the Nazis get their faces melted off.

    2. Re:But... by Randolpho · · Score: 5, Informative

      The article specifically mentions that the sound intensity necessary can only be generated in a super-compressed gas. The sound wouldn't be audible to you at all. Or to your dog, for that matter. It would only exist inside the compression tube.

      --
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      -Marilyn Manson
    3. Re:But... by istartedi · · Score: 5, Funny

      I'm pretty sure that Underwriter's Labs will reject an appliance that melts the user's face off everytime they use it. I've seen their checklist and "[x] make sure face doesn't melt" is on there. So, it will be hard to find any contractor who will install it, or any major department store that carries it.

      --
      For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
    4. Re:But... by homer_ca · · Score: 5, Interesting

      It says compressed gas is needed to generate the sound. All that means is if someone breaks open the fridge it won't keep making 173dB noise. However sound conducts through many materials, solid, liquid and gas. While the chiller is running, you'll still have to soundproof 173dB of noise while taking into account things like heat exchanger tubes.

      How's this for an experiment. Turn your stereo speakers up to the loudest (that's maybe 110dB if you have a killer stereo) and try to build a soundproof box around it that's smaller than your fridge.

    5. Re:But... by victim · · Score: 5, Interesting
      Not quite a proper analogy.
      • Shrink your speakers down to the size of soda can.
      • Realize that this thing operates at a specific frequency and set of harmonics. You are free to use all sorts of resonance tricks.
      • You never need to get inside. You can make a metal casting 23mm thick if you wish.
      • I don't recall reading that his operates in the 20-20kHz range. Maybe its above 20kHz so a small amount of sound leakage is tolerable. (Seems unlikely, but... high-low separation at 20kHz is a fraction of an inch at atmospheric pressure. At higher pressure the wavelength will be greater, so that might give enough space.)

      Suddenly it seems a lot easier to soundproof.

      There is also the issue of the density difference from the compressed gas media in the tube to atmospheric pressure (think about sound not transferring well from water to air or back), but I suspect that is a red herring given that you are going to a more dense material first before the atmosphere.

      Incidentally, I think they have a compressed gas because you can't do 173dB in free air. You rip the air down to total vacuum in the low pressure parts before you get there.

      Unrelated trivia note: Your hearing ends at 20Hz. If you put a mic on your body and pitch shift the 20Hz range up into audible frequencies you will find that your body is quite loud and distracting if you can hear it.
  2. Also on Scientific American by Tyrnagog · · Score: 5, Informative

    Check out their article here. Unfortunately, no mention of peoples' hair igniting.

  3. Oh yeah... by WPIDalamar · · Score: 5, Funny

    If my fridge were to emit some cool Barry White, that's be pretty ... well... cool.

    First there was the "Brown note" ... now the "cool note"

  4. Millions of dollars of research down the drain by Gorm+the+DBA · · Score: 5, Funny
    So, after all those Maytag commercials advertising that their product is the quietest ever...now they'll be advertising "The TURBOBLAST 9000!!! Generates 186 decibels of ear-splitting cooling power!!!!!".

    If this is so cool...how come my constantly loud neighbors haven't turned into icicles yet?

  5. Other ways to do this... by Fnkmaster · · Score: 5, Interesting

    You can also make refrigerators using a Stirling-engine like gas compression cycle. The guys at Medis Technologies have designed this. See here for the brief description. I guess instead of trying to extract mechanical work from a Stirling engine, they are just removing heat from one area and piping it off elsewhere. They claim this uses no greenhouse depleting gases, and it sounds plausible to me.

  6. Re:Cooool by JUSTONEMORELATTE · · Score: 5, Funny

    Sounds of 165 dB would cause a person's hair to catch fire from the frictional heating caused by air undergoing such intense compression and expansion.
    Yeah, but what if I want to keep a human head in my fridge? Won't the hair catch fire and warm up the fava beans?
    --

  7. High-decibel sound by silhouette · · Score: 5, Interesting

    At ridiculous volumes and/or frequencies, sound has some amazingly powerful properties, but I'm skeptical as to how practical such a technology can be. Here's why:

    A professor at my university was doing some personal research with a small team at his house on the properties of high-decibel sound. Based on incredibly complex differential equations, one could project two sound waves at ridiculously high frequencies and volumes to create a special kind of interference. This interference would in essence start a new sound (at a hearable frequency/volume) from where the two waves intersected, effectively making it seem like a controlled sound was being created out of thin air at any point in 3d-space.

    I don't think I need to point out applications to this technology. BUT - he decided to discontinue the project before it was ever completed. He had several pets in his house (dog + cats) that he tried to keep away from the testing, but they were still being driven crazy by the sound. He also started developing nasty headaches and suspected that his high-range hearing was being destroyed.

    Interestingly, one of the graduate students who worked with him on the project decided to continue the work on his own. From what I've heard, he had his work picked up and funded by the US military (DARPA, I think). When I heard this, it really didn't come as a surprise.

    --
    Experts agree: everything is fine.
  8. Re:But they still can solve the *real* problem... by Single+GNU+Theory · · Score: 5, Funny

    No. Global warming is caused by the sun.

    If the sun were to go out, the planet would cool off and die. It would still happen even if we had all the refrigerators on the planet running at 100% duty cycles in an atmosphere composed entirely of "greenhouse" gasses such as carbon dioxide and cow farts.

    BTW, the chlorofluorocarbons you mention are responsible for destroying ozone in the upper atmosphere, which allows more ultraviolet light through. That's a different problem, but related in the sense that now you could have sunburned, farting cows.

    --
    Little Debian: America's #1 Snack Distro!
  9. In other news... by Anonvmous+Coward · · Score: 5, Funny

    ... refrigerator owners in Finland have been court ordered to pay royalties for the sounds generated by the space-age technology inside of their appliances. These royalties multiply depending on how many people are in the kitchen at the time. Hillary Rosen of the RIAA was quoted as saying "First they pirate our music, now they're cooling their food with it? Lots of people everywhere owe us money!"

  10. Re:There hasn't been a DEPENDENCE on those gases.. by 5KVGhost · · Score: 5, Insightful

    By using some combination of these technologies we can move away from environmentally unsafe gases. While this new technology is certainly new and may be superior in many aspects, the only reason we have not moved to more efficient and/or "eco-friendly" designs to date is expense. Welcome to capitalist terra, my friends.

    It's not as though expense can be omitted from the equation entirely. Cheap and easily produced refrigeration technology (and air conditioning, which is closely related) have probably prevented more illnesses than any recent development since antibiotics.

  11. Oh It Hurts! by NeuroManson · · Score: 5, Funny

    "The research is being sponsored by ice cream makers Ben & Jerry's and Unilever. "

    "Humans feel pain when they hear sounds of 120 decibels, a level typically reached next to the speakers at a rock concert."

    So the purpose of this research is to improve on the ice cream headache? Why?

    --
    Just because you can mod me down, doesn't mean you're right. Shoes for industry!
  12. Re:There hasn't been a DEPENDENCE on those gases.. by Tsar · · Score: 5, Funny

    Now we get to one of my pet peeves. Why doesn't any of the major, or minor for that matter, fridge manufactures make a chest style fridge.

    I don't understand your question. All refrigerators are chest style; they only set them on one end in the store so they'll occupy less space. Oh, wait--you aren't one of those idiots that installed it that way when you got it home, are you? Hahahahaha!!! How stupid can you get? I'll bet you put CD's in your PC's cupholder slot too, don't you?

    What a moron!

  13. Get your facts straight by Phronesis · · Score: 5, Insightful
    BTW, the chlorofluorocarbons you mention are responsible for destroying ozone in the upper atmosphere, which allows more ultraviolet light through. That's a different problem, but related in the sense that now you could have sunburned, farting cows.

    CFCs and their replacements, HCFCs and HFCs, are all tremendously potent greenhouse gases. They have global warming potentials several thousand times that of carbon dioxide. The ozone problem is pretty much solved because global CFC production has dropped to near zero following the implementation of international treaties to protect the ozone layer. However, the global warming potential of HFC and HCFC replacements is worthy of concern.

    Global warming is caused by the sun.

    Just as it is true that global warming is caused by the sun, so my body generates most of the heat that keeps me warm. Nonetheless, if I wear too many sweaters, I will get too hot. Taking them off will cool me down, despite the fact that the heat is all coming from my own body. The same principle applies to the atmosphere. The earth's temperature is determined by a radiative balance. We can't change the sun, but we can change the atmosphere (our sweater), and that can cause the earth's temperature to change.