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Making Ice Without Electricity
j-beda writes "Time Magazine is running an article telling us how Dave Williams is trying to make ice for third-world applications using the Hilsch-Ranque vortex-tube effect (first developed in 1930 by G.J. Ranque), where swirling air is split into hot and cold components." The method is horribly inefficient but Williams is hoping it could yield helpful results in areas where electricity is really not an option.
In Winnipeg we just leave water outside for a few minutes.
Trolling is a art,
How about we try and ensure we give them clean water first. The only use for this is in refrigerators and keeping food fresh.
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
useful indeed. (10000000 rpm could be acheivd with mules and huge gears?)
I think that we all know that it's already been tried, and baaaad things happened as a result:
http://www.imdb.com/title/tt0091557/
I don't respond to AC's.
The water leaves YOU outside for a few minutes.
Didn't Dr. Emmit Brown invent something like this back in 1845 or so? You know, shortly before Marty arrived...
How can you rotate anything without moving parts?
The gas moves into the chamber under pressure. The chamber is shaped to send the gas into a whirling vortex. Then the hot molecules go one way and the cold ones go the other. But I think it takes very high pressures to produce the required speeds.
... Time really needs to get its story straight with regards to scientific reporting. This method is a) not innovative b) not practical and c) REQUIRES SIGNIFICANT ENERGY INPUT. Vortex tubes have been around forever, and they are not some form of perpetual motion. It is a well-understood effect, and one which does not violate any of thermodynamics. You put in a lot of energy via compressed air, and get output in the form of a thermal differential. The key point is that you need a lot of high pressure input...where is this going to come from? Electricity. Unless you use a combustion engine to turn the crank on a compressor, in which case that's your energy source. What are villagers in rural india going to do? Blow really hard through the tube?
If you can spin something at 1,000,000 RPM why not spin a copper coil inside a magnetic field and make electricity instead? Quite useful stuff I've heard.
I read the article, and the wikipeda entry, and am left with a question. Without electricity and fule how do we get the compressed gas to run this thing?
We are the Borg...
According to the article this method doesn't require electricity. Then where does the energy to generate the required volume of compressed air come from? Hand pumps?
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Want ice without electricity? Drive the compressor with a small diesel power plant.
Why try to develop something entirely new, with the resulting time and money requirements? A few solar cells + Peltier coolers + some insulation and an ice tray. Yes, Peltiers are inefficient... but they're solid-state, at least, which I think ought to do for remote areas as far as durability. I would think you could assemble a decent mini-freezer out of things portable enough to carry anywhere:
1) Flexible solar panels (less efficient but more portable than glass)
2) A handful of Peltiers... they're pretty small
3) A couple of cans of "Great Stuff" spray-in insulation, or cans of A-B component expanding insulation
One of my friends went to Peru to assemble a non-electric solar water purifier, and anything they couldn't carry on their backs on 30-mile-a-day hikes for a week didn't go. Now that's a design constraint!
1. Wind turbines used to create it and charge batteries at the same time.
2. Solar cells used to create it and charge batteries at the same time.
Inefficiency is in the eyes of the beholder.
-- Tigger warning: This post may contain tiggers! --
Is it just me, or does the fact that an alternative use for this process is the enrichment of uranium seem like a bad idea for the third world (read terrorist training ground)?
How inefficient is horribly inefficient? The gas motors that powers all our vehicles is only 30% efficient, but that's when it's at its peak output (pedal to the metal). Most of the time it averages 17% efficient (17% of the energy generated actually makes it to the wheels).
Couldn't read the full article as it is now "premium content" but if you can make compressed air you can make electricity, and use that electricity for more than refrigeration. The comments about the vortex tubes' inefficiency are correct, so even if you figure the inefficiencies of (solar/labor/water power) to electric then operation of either a freon or Peltier cooler, you are better off.
/ tpad.htm
If someone wants to do something really interesting for the third world, make an adsorbtion freezer using solar concentrators for the heat source. This article discusses some issues: http://me.sjtu.edu.cn/english/scientific_research
The full article seems to be available in the print-only version here:, 1101299,00.html
http://www.time.com/time/magazine/printout/0,8816
You're not missing much, though -- I'm guessing this one was a sidebar blurb, as it's only two paragraphs anyways.
The Romans used to make ice in the deserts of Palestine and North Africa. It seems to me they were around before electricity and Frigidaire.
5 40.Sh.r.html
http://www.madsci.org/posts/archives/nov99/941723
Of course, the large temperature difference between the day and night in the desert it what drives it. That method probably won't work in tropical climates.
-Charles
Learning HOW to think is more important than learning WHAT to think.
The President leaves you in the water outside for a few days.
When he isn't snowboarding or volunteering for Engineers Without Borders, Dave Williams spends his days thinking about something most of us take for granted: ice. As he discovered on a volunteer trip to Haiti in 2002, ice can be a godsend to a poor village, keeping fish fresh on a journey to market or preserving vaccines. But how do you make it without electricity, without access to coolants like Freon or fuels like propane? Williams, 26, knew that forcing compressed air through a hole in the middle of a pipe causes hot and cold air to flow from opposite ends, a phenomenon known as the Ranque-Hilsch vortex-tube effect. No one is quite sure how the separation works, but feed the cold air into a container, he reasoned, and you would have an icemaker and a freezer, which would have zero operating costs and would be environmentally friendly, since it wouldn't require chemicals and the jet of air could be generated via a compressor powered by wind, water, man or animal.
At least that was the idea. Tinkering with heat-transfer equations, Williams tried to determine how much energy it would take to yield a block of ice. "It had been a while since I'd done real math problems. I had to break out the old textbook," says Williams, a product-development consultant with his own firm, Dissigno, in San Francisco. After eons of number crunching, he hit on the right formula and built a prototype. It isn't very efficient; his device uses 35 times as much energy as an electric fridge to make 1 kg of ice. But its simplicity could yield a killer app in Third World villages, where Williams hopes aid groups will distribute his icemaker as an economic-development tool. He aims to field-test it in Haiti later this year. --By Daren Fonda. Reported by Matt Smith/New York
For those who didn't read TFA, and haven't ever read about the operation of these devices, Tim Cockerill wrote his thesis about them. He provides an excellent reference for the thermodynamic operation of these devices. You can put down your tinfoil hats, as they do obey classical thermodynamics perfectly well.
here is a picture of one. it makes it easier to see how it works.
HERE
How can you rotate anything without moving parts???
10000000 rpm could be acheivd with mules and huge gears?
To make that "high rate of rotation (over 1,000,000 rpm)." Better use the ice on your legs after.
If you press a gas into a cylinder with a specific angle, it starts to rotate at a very high rpm. Here is the construction.
Please RTFM first.
Create a 10 mile high structure. Send water to top. Bring ice back down.
Solar cells and windgenerators is your friends :)
My mothers house has 2 ammonia Air Conditioning units built in the mid to late 40's they were "Overage" for a bank and made their way into my grandfathers new home, since it is a hot water heated house its great, let me tell you these things will even chill the upstairs of the house , at 2000 ish square feet to push cold up is not a bad trick, the volume they output is the key.
:) Designed well, and built like German tanks...
The funny part ? They still work flawlessly, and have not been serviced since at least 1977 ( In know this for a fact as thats when my grandad passed away)
Their electric consumption is actually minimal, running both all month equates to about a 60$ electricity increase. Unreal if you ask me, I kept thinking we were on an electric budget the first summer I fired em up in 20 years as it was way to hot for my grandma without air so I told her I would cover the bill. it never went up....
The beauty is these units will spill the ammonia outsie through the exhaust should the coils ever rupture (I doubt it since they are about 1/8 in thick copper
Forget your wedding anniversary.
Works every time!
What?
For an interesting look at a time before refrigerators when ice was cut from lakes in North America and shipped around the world, read Gavin Weightman's book The Frozen Water Trade.
Back when I lived in an African village, 1989-92, we had a kerosene refrigerator. All I had to do was trim the wick occasionally and keep feeding it fossil fuel and it kept things cold/frozen for me. A co-worker of mine in another location converted his to burn butane by putting a bunsen burner in place of the kerosene wick.
Although we certainly used our fridge for food and ice, it was also very important to refrigerate meds for the clinic in our village.
Making ice without any electricity happens everytime I try to talk to a girl.
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I prefer the elegant simplicity of two grossly different sized gears.
Of course, if there's no wind, you're fscked.
If someone wants to do something really interesting for the third world, make an adsorbtion freezer using solar concentrators for the heat source.
And while you're at it, a solar concentrating mirror (or foil arrangement), without a greenhouse-forming glass layer, pointed at a cloudless night sky, makes ice REALLY well.
The night sky (absent clouds and above the atmosphere) is four degrees absolute - and it's not THAT much warmer from ground level even with the mostly sub-zero greenhouse gas layers floating above. With mirrors or foil to redirect the light/infrared so that the container of water (or coolant) "sees" night sky on all (or most) directions and reasonable shelter from air currents, a container's black-body equilibrium temperature is far below freezing. It heads for that temperature quite quickly if it is painted a dark color.
People have been making ice on calm desert nights using this principle for centuries.
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No wonder they stopped making them. They were putting plumbers and stores out of business with durable and reliable air conditioners
http://www.dhs.gov/dhspublic/interapp/editorial/ed itorial_0566.xml
"When an incident or potential incident is of such severity, magnitude, and/or complexity that it is considered an Incident of National Significance, the Secretary of Homeland Security initiates actions to prepare for, respond to, and recover from the incident." (NHP, 15)
"The President leads the Nation in responding efficiently and ensuring the necessary resources are applied quickly and effectively to all Incidents of National Significance." (NHP, 15)
"Standard procedures regarding requests for assistance may be expedited, or under extreme circumstances, suspended in the immediate aftermath of an event of catastrophic magnitude." (NRP, 44)
I hate to sound cynical, but I don't think it's the federal governments job to provide evacuation before a catastrophe. If mayor ray is so in touch with the plight of the common man, maybe he should've actually provided a way out of the city for people who could not come by their own transportation. He could use school busses and what not.
But besides that, the super-dome was engineered to withstand a hurricane, and had food and supplies for thousands of people. What they didn't count on was that levies would breach and people would be stuck there for a long time. That means they had no plan to get people out of the super-dome once they were there.
And no, the government can't just pick them up and move them at a moment's notice. When the military deploys overseas, it is the result of months of planning and preparation. Not to mention that a large scale deployment requires access to at least a well developed airfield, and preferably the ability for ships to dock and deploy equipment and personnel. New Orleans had neither at the time of the emergency.
In the face of a lack of necessary planning and preparation we were left in a situation where thousands of people were left for days to fend for themselves while several levels of government made an uncoordinated attempt to provide aid.
To say that this disaster had something to do with how some people might vote is disgusting, offensive, and ignorant. You should try-thinking for yourself once and a while instead of just reading and regurgitating what you read on BBC.
"The ammonia does not boil.... Ammonia and water are boiled in the boiler ..."
You might want to be a little more careful not to contradict yourself when "correcting" somebody.
The total system pressure sets the temperature at which the boiler will have to run to boil the ammonia/water solution - so to use a low grade heat source you would have to run a lower system pressure in order to allow the low grade heat to boil the mix and run the cycle.
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