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Thermoacoustic Cooler Means Green-Friendly Icecream
MuddyRiverDoc writes "National Public Radio aired a story describing ice cream
manufacturer Ben & Jerry's sponsored
development of a thermoacoustic refrigeration technology, which uses helium gas
subjected to ultra-loud 173 db sound to chill an ice cream cooler. The NPR interview and
pictures of the Penn State researchers who did the development is
available. There is also a brief description of the technique at the Penn State Live site and at the BBC, and an
over-cute Ben & Jerry's broadband presentation, Sounds Cool!, that
does however provide a useful diagram. Thermoacoustic refrigeration has been a focus of research
for more than a decade at Purdue
and elsewhere,
and has reportedly flown on the Space Shuttle, but this prototype is reportedly
the first that demonstrates the size, efficiency, and quiet operation that
promises successful commercial introduction. Cool Sound Industries,
Inc. is reportedly exclusively licensed for this thermoacoustic technology."
So does this mean that noisy, drunken parties will be cooler than quiet, staid cocktail parties?
Great minds think alike; fools seldom differ.
wouldn't the sound polution kinda reverse the positive environmental effects? and dont tell me to RTFA.. there were too many links, I didn't know where to click :|
Ever see people driving down the street with their radio so loud their car buzzes. They're pretty cool right?
Need a Catering Connection
The sound that would send the necessary amount of "green-friendly" chills down the spine of any helium-cooled refrigeration unit is Howard Dean's famous scream.
I really miss a microwave fridge in my kitchen
Now I can buy that new kick-ass sound system without worrying about that new fridge my wife has been hounding me about and not feel guilty!
It's hard enough to remember my opinions, never mind the reasons for them..
Alright! So if I climb in this thing and shut the door.....
I heard this interview on the radio. Apparently the process doesn't save any energy. It doesn't use ozone depleting chemicals though. Unless it ends up being much less expensive to manufacture I doubt it will go anywhere.
"God fights on the side with the best artillery." - Napoleon, Marshal of France - speaking truth to power
Out of curiosity, is there a reason why peltier coolers haven't been more main stream? I even have a small cooler that uses one, but it seems the idea of making it into larger appliances is something not which of thought.
Bel, the mostly sane.. "Of course I can't see anything! I'm standing on the shoulders of idiots." -- Me
When Unilever bought them out, most of us (shareholders, that is) assumed B&J's would get folded into the corporate machine and lose some of its identity. It's good to see that they've sort of remained a seperate entity that just happens to be owned by a corporate giant.
I'm too lazy to RTFA and the writeup was full of links but short on information.
Can someone tell me what this is all about? Is there a chance I can get indignant and rant about something I have neither the time nor patience to understand?
and quiet operation
If 173 dB is quiet for you, I'd hate to be around when you throw a rock concert! Liquified bones are not my idea of a good time!
And did anyone read that as
the Penn State researchers who died in the development
? I must need a couple more hours sleep...
8-PP
"Yo B, turn that sh*t down..."
"Naw man, it's cool...just makin' ice cream"
"Word"
Wise men say, "Forgiveness is divine, but never pay full price for late pizza."
So they've taken "We all scream for ice cream!" literally?
Inside the canister there's 198 Decibels going on... That would shatter your ear drums and make your eyes bleed (possibly) pretty quick I understand...
Outside the container all your hear is a regular humming noise at one frequency...
If you ignore the other uses of a tool, does that make the tool less useful, or you less useful?
It's also possible that in the drive towards production, the system could be made more efficient. As I understand it, the goal so far has been to get it working. That goal has nothing to do with energy efficiency.
The next goal is or should be ramping up production after long-term testing... After that the goal of energy efficiency can be worked on.
If you ignore the other uses of a tool, does that make the tool less useful, or you less useful?
If you suck the freon out of your conventional freezer it will kill you too. If you'd RTFA you'd know the sound waves are contained in the cooling chamber ond only a dull hum (comparable to a normal fridge) is heard.
Hi, I live in Canada and I've always wondered why we didn't have a fridge that would take advantage of the outside temperature ? I mean, when it gets down to -20s celcius and you spend a lot of energy heating your house to +20 celcius, then you spend some more energy to cool down the fridge inside the house (although it actually participates in heating up your house), it sounds kind of ridiculous, don't you think ? Is there a particular reason for this ? Maybe it wouldn't be of much use for anyone but canadians, russians, norvegian and the like, but still... I've always known there was a link between noise and temperature... After all, my fridge sure is noisy !
IANWYTIA (I Am Not Who You Think I Am)
Barry White.. cool
Cindy Lauper.. not cool.
- these are not the droids you are looking for -
173dB is quiet? Was your previous job in the PR department of a CPU fan manufacturer?
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
And its probably good marketing . . . keeps the "socially concious" brand reputation.
This may be the first technology where yelling at a piece of broken equipment really loud makes it work?
toresbe
"thermoacoustic refrigeration technology, which uses helium gas subjected to ultra-loud 173 db sound."
I know...RTFA, but...I did read the FA. Problem is I must have read the wrong one (so many links here.)
Whatever they use to keep the 173db sound locked inside the box, I want. I'll use it to line my appartment walls, as I'm tired of hearing the latest crap..err...latest top 40 hit being blasted by my neighbor's juvenile deliq..err...teenager.
There are lies, damned lies, and statistics.
A class I was taking last semester was being taught by a retired NASA program manager who mentioned the helium scarcity. Most of the world's helium is "mined" in Texas, so if this were handled correctly it could lead to quite the litte technology monopoly. OTOH, if helium were to become more scarce on earth I pretty sure someone would find an alternative source.
"God fights on the side with the best artillery." - Napoleon, Marshal of France - speaking truth to power
Reported maximums (research-only included) in terms of Carnot efficiency:
Stirling-cycle (phase-change): ~50%
Peltier junction (solid state): ~10%
Thermoacoustics (standing wave in gas): ~40%
Using a 'speaker fridge' now would be quite wasteful in terms of efficiency, although researchers believe that they can surpass the old CFC-type compressors soon.
The question that comes to my mind, though, is why the focus on the cooling itself. For a non-emissive object like ice cream, better energy conservation may be more easily achieved through better insulation. How about investing in cheaper silica aerogel, hippies? This stuff is virtually as light as air, essentially made of sand, almost as insulative as pure vacuum, and fairly strong. Having a cooling engine without any ozone-depleting chemicals is great, but it's kind of silly if your freezers still have interior styrofoam lining.
There already is a climate-friendly alternative, GreenFreeze. And the Europeans that have adopted this technology (despite the fact it was heavily pushed by GreenPeace) have a lot of experience making very energy-efficient appliances.
Unless they expect this to be cheaper/ more efficient, I can't understand why they would finance such research- except as publicity.
Information: "I want to be anthropomorphized"
First off, the 190db figure is the sound level INSIDE the unit. Acording to the reporter, the sound level outside the unit was no louder then a standard cooling unit.
From the description of given, the tech sounds interesting. They use a powerfull speaker to create areas of high and low preassure in the chamber. In the areas of low preassure they place tubes which run to the cold case. In the areas of high pressure they place tubes which run to an external heat exchanger to vent the waste heat.
I can definately see this technology comeing into widespread use in the future, as stricter enviromental controls continue to restrict conventional refirgerants. I also wonder how well it would work in an automotive setting, where the high level of vibration makes coolant loss more of an issue.
- How eco-friendly is the helium extraction process? Off the top of my head I believe it's fine, but are there any hidden eco-hostile effects in its production? Probably still far better than the method it replaces.
- Have they experimented with different sound sources for the 173dB? Playing Barry White could produce seriousness smoothness...
- Will they equip the Refrigerator Gnome that controls the internal light with OSHA-approved protective headphones, or will a generation of the little critters be doomed to deafness? (Don't laugh, I saw one of them in my 'fridge once after a Dead concert.)
I always liked these - not too hard to make, but also not as effecient as other methodes. Apply compressed air, tube gets hot on one end and cold on the other.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
The news is expected to have a chilling effect on listeners, particularly when the volume is turned up.
Astro
The reason you don't have ammonia in your car and home is that exposure to the chemical in concentrations above 300ppm poses health risk. 30 minutes of exposure above 1720ppm can cause death and 5,000ppm is rapidly fatal. It should never be used in a run-to-failure, zero maintenance system like your kitchen fridge or AC unit.
Simple people talk of people, better people talk of events, great people talk of ideas.
Could a thermoaccoustic AC unit be created? Sure, but it won't fix the problem of 3rd world AC. The electricity costs of a Thermoaccoustic AC unit would actualy be HIGHER then the costs for a conventional unit.
The issue here is not energy-efficency, it's abandoning ozone-depleateing refrigerants.
Themoacoustic coolers can probably be produced with a much higher mean time between failure as well. Fewer moving parts. I assume they could make a long-life speaker cone and make it replacable with a "slide out, slide in, recharge gas" type fix.
The end result is fewer fridges go to landfills beause they broke.
Even if the average lifetime of the fridge can be raised by a few percent, that's significant reduction in appliance-garbage.
Doesn't quite work that way. The reason why you have problems with noise is that speakers are intentionally designed to propogate sound. When sound waves hit your walls the walls resonate and pass along the sound. The refrigerater is quiet to the external world because the compression chamber is designed exactly so that the sound waves reflect and cancel in exacting positions inside the chamber. There is no excess accustic energy left to leave the chamber. This can only be done because the sound waves generated are exactly the wave length that matches the distance inside the chamber necessary to cancel. In other words, if you could "build a wall of it," it would only stop one exact frequency. What you really want is accustic foam that is designed to stop a wide frequency range of sound. This is commonly used in studios to prevent echos off the walls that give the "recorded in a box" sound effect.
Bel, the mostly sane.. "Of course I can't see anything! I'm standing on the shoulders of idiots." -- Me
The key difference between helium and argon is density. Helium is (obviously) lighter than air, and when released, floats to the top of the atmosphere. Presumably some evaporates into interplanetary space, given the energetic environment, there. Argon is denser than air, so it will tend to stay in the lower atmosphere.
Both are fossils of creation, but helium is also generated by alpha decay of radioactives inside the Earth. (Alpha decay particle steals two electrons from an unsuspecting nearby atom and presto, helium.)
If there were enough desire for helium, it might be possible to scoop it from the upper atmosphere. There has been talk of space planes running an oxygen liqufaction cycle for an 'air-breathing rocket'. If we can actually do that, we're halfway to mining helium. Helium would be part of the stuff that *didn't* liquify on the first part of the cycle.
The living have better things to do than to continue hating the dead.
The whole point about CFCs in fridges is that they are sealed in a closed loop {compressor - condenser - evaporator}, therefore, not able to damage the ozone layer until the fridge is disposed of {or you have an accident while defrosting with a chisel .....} The usual way of getting rid of CFCs is to wait until nobody is looking, then discharge them into the atmosphere. Practically speaking, there's not a lot else you can do with them anyway. So if you have a CFC-based fridge and it's still working reasonably well, you should hang onto it -- as long as it's not being abused, it won't be using significantly more energy than a more modern one would, and manufacturing a refrigerator uses up a lot of energy {which also is conveniently forgotten}. If it cost x kWh to make in the first place, and saves y kWh per year compared to the old fridge, it needs to last for x/y years before you have actually made any saving -- if it packs up before that time limit, you actually lose out on the deal {assuming the old one would have survived that long; but older kit was built to last forever, whereas newer stuff is built to pack up after awhile}.
..... so the contacts will stay closed and not spark. If anything does set off an explosion, it won't be the fridge itself.
My new fridge {purchased in a hurry after a defrosting accident last year involving a chisel, the evaporator and a faceful of evil-smelling chemicals} uses iso-butane -- cigarette lighter and camping stove fuel -- as its refrigerant. It's sealed in the pipes, so there is no danger of an explosion. Even if the pipes do start leaking, the thermostat won't be satisfied -- no matter how long the motor runs {trying to cool down the sensor} it won't get anywhere because there is no pressure, so no cooling
Je fume. Tu fumes. Nous fûmes!
But once the ammonia dissaptes into the atmosphere there is no lasting, negative effect. This cannot be said of HFCs and CFCs. Heck, this probably can't be said for most of the chemicals under your sink or in your auto. Farmers plow thousands of pounds of ammonia into the ground every year. Thats what I meant about environmentally safe.
With respect to the rail car, with ammonia you will think you are going to die from the pungent odor long before you suffer any ill health effects. i.e. ammonia causes lawsuits long before it causes any health problems. OSHA's Permissible Exposure Level is 50ppm. That means the average Joe could work 8 hours/day 40 hours/week for a lifetime with no ill health effects at 50ppm. To give you some referece, chopping a strong smelling onion is similar to exposure to about 10-15ppm of ammonia.
With respect to your serin gas analogy, consider water. Water is also fatal in certain quantities but I am certain that it is still environmentally safe.
Simple people talk of people, better people talk of events, great people talk of ideas.
Apparently thermoacoustic refrigeration works better in orbit because in space, no-one can hear ice cream.
As one of the inventors of this technology, I want make certain that readers understand that COOLSOUNDS and Kieth Franklin are NOT licenced, are UNRELATED, and are NOT IN ANY WAY ASSOCIATED WITH THE PSU TEAM !
1: invade Iraq.
2: Steal the Oil
The US did not invade Iraq to steal oil, for a number of very obvious reasons:
Please...It's getting ridiculous that so many people still believe that this is a war for oil when the numbers didn't add up before the war and still don't add up after the war...
The story reminded me that Einstein and Szilard obtained patents on various thermoacoustic refrigerators.Is this a refinement of that?
The clearance system sounds logical. It is not. It is completely arbitrary. -- John Bolton