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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!"
Reduce the gases that contribute to global warming, but contribute to noises that drive Fido mad...
</senseless humour>
Check out their article here. Unfortunately, no mention of peoples' hair igniting.
If my fridge were to emit some cool Barry White, that's be pretty ... well... cool.
... now the "cool note"
First there was the "Brown note"
If this is so cool...how come my constantly loud neighbors haven't turned into icicles yet?
You know, that sounds way more fun that cooling some ice cream. Or maybe I've been playing too many videogames.
Err wait a minute, they're cooling with sound...ummm nevermind. Move along.
Trolls lurk everywhere. Mod them down.
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.
What I find more interesting than the projected "energy" savings (which I would have to see the science and the experimental data before I'd bank on), is that there is no compressor to wear out, no refrigerants, etc. Conceivably a service call would be something on the order of "open the sound box, unclip the sound driver, put in a new one", right?
I wonder what the heat output on the hot side is -- enough to supply a home's hot water needs, perhaps?
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
"Refrigerators To Cool With Sound"
So what. I live near the Capital of Washington State. We plan on heating our homes through the use of political speeches!
The race isn't always to the swift... but that's the way to bet!
But it's possible to use ANY compressable gas for cooling. The ones we use now are simply very efficient because they can store a lot of heat. There are several ways to make a cooling system more efficient (at removing heat) assuming you have not already taken the particular step to the maximum.
Of course there are two heat exchange systems in a typical refrigerator; Those inside which are intended to absorb heat, and those outside which radiate it. In a peltier-cooled system the same heat exchanger(s) do both jobs. You also end up needing some kind of heat sink to increase surface area since the thermally active portions of peltier coolers are flat.
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.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The dominant effect of CFCs was to eat away at the Ozone Layer. However, CFCs are also greenhouse agents and actually far better at it than CO2.
Most of the compounds we have now introduced to replace CFCs are also greenhouse agents.
Best wishes,
Mike.
Global Cooling has been developing more efficient (and safer) CFC-free refrigeration and cooling (even cryo-cooling) systems for quite awhile, now.
=Smidge=
BZZZZZZZZZZZZZZZZZ
What did you say?
BZZZZZZZZZZZZZZZZZ
I asked if you'd like a cold beer.
BZZZZZZZZZZZZZZZZZ
Seriously though, I've seen a demo of this technology about 5-6 years ago and It's pretty cool.
JET Program: see Japan, meet intere
Except the dB scale is logarithmic.
+3 dB = 2 x as loud
+10 dB = 10 x as loud
53 = 10 + 10 + 10 + 10 + 10 + 3 = 10*10*10*10*10*2 times as loud = 200000 times as loud. So actual its much more than "tens of thousands"
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?
--
and obviously, chip cooling. I always thought loud music was cool.
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
It was developed at Los Alamos.
"I assumed blithely that there were no elves out there in the darkness"
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.
refregerators are one thing, but I see this being a good application for roof mounted HVAC equipment. which is noisy anyways and are usually mounted in remote locations. This also applies to most commercial walk freezers/coolers. They all use a remotely mounted condencing (cooling) unit. My biggest questions are 1.) weight 2.) power consumption. I imagine this would remove the need for a compresser and radiator type vents making it lighter.
You know what I want? A fridge built into my countertop that pneumatically raises up at the touch of a button, leaving all the cold air still down in the refrigeration pit. It'd work just like your adjustable office chair. Yes, I know it would be a pain to clean when your cat knocks half a jug of juice down there, but isn't that a price worth paying?
Think about it... *whoooosh*... makes those 1950's techno-utopian dreams look almost attainable!
Wah!
"1. ...Of course it does raise the cost of opening the refrigerator door, in comparison to the cost ratio now. ..."
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. There are many chest style deep freezes, but no fridges. With a chest style fridge you'd only loose very little of the cold air in it when you opened it, rather than dumping darn near every bit of cold air out onto the floor as with the cabinet style fridges.
Just my $0.02
"Oh drat these computers, they're so naughty and so complex, I could pinch them." --Marvin the Martian
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!
We all know that ultra low frequencies can cause your bowels to, well, kick in and empty out, right? I wonder if you can buy a package deal - combo 'fridge/toilet. Kick in a TV, padded/heated seat on the toilet, and you've pretty much just created the ultimate guy Christmas present.
I've often wondered why a two piece conventional freon refrigerator never caught on. You could place the compressor, condenser, and the support structure outside the house connected with two hoses (same as your whole house AC). This would eliminate most of the internal noise and be far more efficient as you are not releasing the hot air from inside the fridge + the electrical and mechanical losses into the house. In the fall through spring season cycle it would even be more an advantage as it is often much cooler outside then in the house and the compressor could even be bypassed. This would allow for smaller, quiter, and higher efficiency refrigerators and allow more flexibility as you could replace the inside and outside units seperately when and if needed. The inital conversion would be a little higher because you'd have to run lines and a concrete pad or wall hanging device outside but long term it would be much less. Installation in new construction would be simple. Anyone have some VC money they want to get rid of?
Bad boys rape our young girls but Violet gives willingly.
... 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!"
I feel compelled to lay to rest all of these posts about people going deaf from these refrigerators...
Thankfully, even if the fridge cracks open the vast sounds generated within will not escape because the intense noise can only be generated in the pressurised gas locked inside the cooling system.
Think about it for a moment. To generate the 120 dB in front of the speakers at a rock concert, you need some serious wattage. Those are powerful blasters, my friends. Also realize that the Decibel scale is logarithmic, meaning that the amount of "sonic energy" or volume -- whatever you want to call it -- between say 20 and 30 dB is a lot less than the amount between 120 and 130 dB. We're talking about a difference between 120 and 173 dB, which is, as the article points out, "tens of thousands of times more intense than any rock concert." I'm not a physicist or anything, but I'd assume that's why the sounds generated in the cooling unit work within a highly pressurized atmosphere -- so the sounds can (1) be created more efficiently and (2) carry through the gas properly. Open the unit into normal air and I don't believe it works anymore -- the atmosphere is too thin to produce those kinds of levels. On top of that, the unit is probably insulated in a vacuum anyhow, so as to prevent sound from escaping.
You won't go deaf. Your animals won't go crazy. The most you'll probably ever hear is a soft hum.
On Slashdot, we don't say "thank you." We say "that's enough..." -_-;
Global Cooling on the otherhand produce rival products to Medis El based on the Free piston Stirling Engine.
Despite being some impressive technology, Free Piston Stirling Engines haven't really been taken up to well. Its a shame because they do seem to be much more efficient.
If you are really interested then you might want to check this out At Ames Lab. Gschneidner's work on the giant magnetocaloric effect is REALLY impressive. Its all about the exchange of entropy between magnetic and kinetic forms. Damn cool.
- This and all my posts are public domain. I am a Physicist. I am not your Physicist. This is not Physically advice
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.
"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!
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!
A small team of 10 or so in conjunction with Lawrence Livermore National Laboratory built a thermo-acoustic refridgerator. It didn't work to well but it sure did make a hell of alot of noise. :)
Our most successful aspect of the project was the prototyping of the stack. We discovered that a form of carbon areogel had some very cool properties that made isolating the heat exchanges easy. To test the new stack we created a "hooter-tube" (or holfer tube) which is the opposite of the refridgerator. We created a difference in temeperature to generate sound. We dipped one end of the tube in liqued nitrogen and then heated the other end with a blow dryer. It was a blast to play with becuase it was about the size of a light saber and becuase the open end was the cold end the air around the tip would condense and allow you to "see" the sound wave (well, a quarter of it anyway).
here are some photos and other stuff:
photo of hooter tube
photo of working refridgerator (very similar to ours)
Navy page with lots of info
BUNNY OF DEATH!
Certainly expensive refrigeration wouldn't solve problems for the impoverished. Of course lots of people in the world STILL don't have refrigeration, which (as anyone who has played civilization 2 knows) lets you produce more food because you can store/transport more.
On the other hand for most of the world it makes sense to purchase initially expensive refrigeration hardware because it will save on costs in the long run. It regularly pisses me off that it is generally impossible to get a refrigerator with a basic set of features (IE, no ice maker/crusher, no water spigot, no computer in the door) without industrial-quality insulation.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
On the other hand if the gas is compressed farther it will be able to accept more heat, so you should be able to get a more rapid heat transfer
Sorry, it's been a few years since I had thermogoddamics, but I'm not sure this is correct. The heat transfer uses ENTHALPIC heat, which is given up or absorbed when the material changes state. In other words, Freon (ammonia, whatever) absorbs heat when it changes from a liquid to a gas, and vice versa. You compress the gas JUST ENOUGH to change its state to liquid, compressing it further has no effect (besides, compressing liquids isn't really practical anyway.) I believe what makes the Freon family so suitable for heat exchanging applications isn't it's enthalpic heat capacity, but the temperatures and pressures at which it changes state, i.e. practical in real-world terms. For example a compound that changed from gas to liquid at 2000 PSI at -140C wouldn't really be useful for much of anything. Some substances don't go through the liquid stage at all at practical pressures (carbon dioxide)... they go straight from gas to solid (and vice versa). Hard to pump a solid through a heat exchanger.
Anyway, you made some great points, but the solutions may not be as practical or simple as you suggested.
And I didn't see any mention in the article of what kind of compressed gas was used in the sound chamber.... Freon maybe? haha.
To ensure perfect aim, shoot first and call whatever you hit the target
At last, a fridge that goes to ELEVEN.
This research made some noise (ha!) about ten years ago. A company called Macrosonix holds the patents. Even NPR has covered this in the past ten years.
The best explanation of the technology I've seen is in "Fluid Power Journal."
Marketing guy: Great! So we have Michael Jackson as a customer. Who else are we going to sell this thing to?
**RIMSHOT**
Thank you! Thank you! I'll be here all week!
That is all.
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.
What I would really like to see is a house designed around a centralized heat reservoir. Dump the heat generated by your Fridge and your AC into a stack where your water heater, your over, and your Heater can pull from. Obviously you'd also want a heating element there, but the energy savings of recouping the heat from the other applicances would be significant.
Kind thoughts do not change the world
I can't remember the name of the program, but it was one of those "Look what's new in science" type programs on the Discovery Channel. On this one I remember, I saw them talking about a sonic fridge. This was 10 years ago. They had a prototype 10 years ago. What happened to that?
HELLO?
Is your refrigerator running?
WHAT?!?
Is your refrigerator running?
WHAT?!? YOU'LL HAVE TO SPEAK UP!
Oh nevermind.. *click*
Hmm, no units, maybe it's Kelvin. That would be really impressive. :)
I read the internet for the articles.
The article claims that 165dB is sufficient to cool a refrigerator - my neighbour's daughter exceeds that by a long shot. Does this mean we can put her inside a tube and get her to keep my beer cold?
.. bear in mind one thing: cost. Obviously any innovative solution that is ecologically sound is good and all, but the worry is that the uptake in 3rd world countries would be slow.
The new fridge might be more reliable and does not pollute, but the old technology has an army of technicians who can service it, and I believe countries like China are still allowed to produce CFC coolants. In fact, when countries agreed to phase out CFC, China's phase-out was based on its production several years in the future, and as a result its production actually jump in the subsequent years as manufacturers took advantage of the loophole.
More information here
Michel
Fedora Project Contribut