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Making Ice Without Electricity
Posted by
ScuttleMonkey
on Mon Sep 12, 2005 03:02 PM
from the old-science-becomes-new-again dept.
from the old-science-becomes-new-again dept.
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.
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High-Tech Electro-Defroster 109 comments
DahBaker writes to mention a News.com story about an ingenious way to de-ice a surface. From the article: "Dartmouth College engineering professor Victor Petrenko, not to be confused with one of the Champions on Ice, has devised a way to use a burst of electricity to remove ice caked on walls or windows. For surfaces coated with a special film, the jolt gets rid of ice in less than a second, far less time than it takes to hack at it with an ice scraper. While drivers might find easy-cleaning windshields convenient, the technology--called thin-film pulse electrothermal de-icing, or PETD--could have significant economic impact if widely deployed. It could, for example, cut the costs of repairing power lines downed by ice storms and keep plane windshields frost-free, decreasing fuel consumption."
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Hrm. (Score:5, Funny)
In Winnipeg we just leave water outside for a few minutes.
Re:Hrm. (Score:5, Interesting)
If you build a solar reflector, but only employ it at night the items inside will become cold, and can attain temperatures below freezing.
Doesn't work as well on cloudy nights (you are essentially 'beaming' the heat out into the great heatsink called space) and it has to be well insulated from the environment around it (ground, air, etc).
-Adam
Re:Hrm. (Score:5, Informative)
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In September 1999, we placed two funnels out in the evening, with double-bagged jars inside. One jar was on a block of wood and the other was suspended in the funnel using fishing line. The temperature that evening (in Provo, Utah) was 78 F. Using a Radio Shack indoor/outdoor thermometer, a BYU student (Colter Paulson) measured the temperature inside the funnel and outside in the open air. He found that the temperature of the air inside the funnel dropped quickly by about 15 degrees, as its heat was radiated upwards in the clear sky. That night, the minimum outdoor air temperature measured was 47.5 degrees - but the water in both jars had ICE. I invite others to try this, and please let me know if you get ice at 55 or even 60 degrees outside air temperature (minimum at night). A black PVC container may work even better than a black-painted jar, since PVC is a good infrared radiator - these matters are still being studied.
I would like to see the "Funnel Refrigerator" tried in desert climates, especially where freezing temperatures are rarely reached. It should be possible in this way to cheaply make ice for Hutus in Rwanda and for aborigines in Australia, without using any electricity or other modern "tricks." We are in effect bringing some of the cold of space to a little corner on earth. Please let me know how this works for you.
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This is an experiment you can conduct yourself. It may be that without advanced insulation (maybe straw wasn't enough?) one couldn't obtain ice in the desert, but given good modern materials the physics suggests that it would work well.
-Adam
Re:Hrm. (Score:5, Funny)
Rollin', in my 5.0 with the top left back so my hair can blow...
I dunno. Let's find out.
Rollin'... in my 5.0,
With my rag top down so my hair can blow,
The voltage is on standby, costs of icin' too high,
(Did you stop?) No, I just froze, by
Freon - pursuin' temp'rature drop,
Compressor's dead, yo, so I continued to,
George J. Ranque, Hilsch-Ranque vortex tube!
Peltier's hot, like electrical bikinis,
And I got no voltage from the Lamborghinis,
Warmin' - cause I'm out thawin' mine,
Got my compressor gauge, readin' PSI "9"
Vaccuum - for the mods on the wall,
Mods are actin' ill because they had their 8 LOLs
Hissin' - through the compressor shell,
I clamped the hose, but it was shot to hell,
Ozone - burnin' up like real fast,
Registration link at time-mag suckin' goat ass
Readin' the Wiki, the 'pedia's packed,
Thermodynamics 'bout how the fridge is jacked.
Third law on the scene - you know what I mean,
A million RPM? Efficiency is unseen,
If it's a solution, this don't solve it
Pump out the heat while the Hilsch-Ranque revolves it
(Vanilla) Ice Ice Geeky, too cold...
Re:In Soviet America... (Score:5, Insightful)
After all, any fool knows that a catagory 4 hurricane, broken levee's, 10 feet of flood water, and the breakdown of social order shouldn't require any pesky government meddling to deal with. Just gutsy individuals with a can-do attitude!
Those dang people should quit whinging and get over their "victim" mentality.
Re:In Soviet America... (Score:5, Insightful)
First of all, the states asked for aid, and Bush signed a state of emergency, BEFORE Katrina hit. There was no question about authority. FEMA and the federal government had all the authority and responsibility in this situation.
Secondly FEMA dropped the ball so badly because we have had five years of a government that thinks just like you do. The Bush adminstration has so little respect for government agencies that they choked them with insufficient budgets and apointed unqualified cronies to run them, forcing out experienced disaster management people. Read the recent columns by Paul Krugman and Thomas Friedman in the NYT for lots of details.
Is it any wonder New Orleans got the response it did with the leaders we have?
Clean water first??? (Score:5, Insightful)
Re:Clean water first??? (Score:5, Insightful)
Re:Clean water first??? (Score:5, Informative)
1. A freeze/thaw cycle kills many (not all) microorganisms--ice crystals shred cell membranes, and freezing can mangle the protein coat on viruses. A number of tropical parasitic organisms aren't well adapted to the cold, either.
2. You can remove some dissolved chemical contaminants if you don't freeze all the water. As water freezes, the assembly of regular ice crystals tends to force impurities out into the remaining liquid. If you stop after you've frozen four-fifths of the water, then you can throw out that last twenty percent that contains the concentrated contaminants. Ice that forms on bodies of salt water is almost pure water, because the salt is driven into the liquid phase by the freezing process.
Already done! (Score:5, Funny)
http://www.imdb.com/title/tt0091557/ [imdb.com]
Re:Already done! (Score:5, Funny)
I read TFA, and... (Score:5, Informative)
Re:I read TFA, and... (Score:5, Interesting)
I make ice and keep things cold EVERY time I go camping without electricity. in fact I make a fire to make things cold.
that type of freezer/fridge has been around for decades and are pretty efficient now compared to electric units.
I use maybe 10 pounds of Propane to run my RV fridge for 3 months straight.
I'm all for inventing new ways of doing it, but to "help the poor in africa" is not the way to try out new stuff.
give them a fridge with a coil plate they can build a fire under or will allow an oil lamp burner to keep it running (yes this works) and use that old tech that simply works.
Why not just make electricity? (Score:5, Funny)
Re:Why not just make electricity? (Score:5, Funny)
There's a reson why electicity is a freakin' universal component of modern societies people. It's EASY to produce, so easy that's it's just about goddamn trivial since there's dozens of different ways to go about it, and NONE of them involve ridiculously ineffcient and complex methods like "ice without electricity" does.
Hell, why not work on "masturbation without enjoyment" too, that should be just as useful.
Re:Why not just make electricity? (Score:5, Informative)
Or, we have found First and Second Prize winners in the "Talk out your ass without knowing anything" game.
If either one of you had bothered to look into this device for even a moment, oh I don't know, maybe here [cockerill.net] for example, you'd know that they aren't spinning anything at a million RPM. It is a device that has no moving parts. Basically, and I'll boil it down for you, you blow in one end and two streams come out, one hotter and one colder. It's the vortex inside that can reach a million RPM.
If you can find a way (and this, I assume, is what he's still working on) to get enough air through it then you can get the cold stream very cold indeed, which is useful.
I've never been to anywhere that qualifies as Third-World, but I assume that simple is better. With no moving parts this is as simple as it gets, if a way can be found to get enough gas through it. Perhaps it's wind, or volcanic gases, or storing composting gas, or simply the hot air generated by your armchair engineering, the point is that he's looking into it to try to help people, and you didn't look into it and are helping no one.
Why not use electricity? (Score:5, Insightful)
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
Reinventing the wheel? (Score:5, Informative)
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
Re:Reinventing the wheel? (Score:5, Funny)
All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, public health, and making ice without electricity, what have the Romans ever done for us?
Physics of Ranque-Hilsch Vortex Tubes (Score:5, Informative)
here is a picture of one (Score:5, Informative)
HERE [google.com]
Nothing New! (Score:5, Funny)
Re:New definition of "moving parts" (Score:5, Informative)
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.
The big question is... (Score:5, Insightful)
Re:Why not gas absorption? (Score:5, Interesting)
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