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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.
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.
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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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
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
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.
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?
Some people actually rely on the government instead of thinking and acting for themselves.
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.
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Local and state governments were thoroughly incompetant, and FEMA was unable to force their way in thanks to that pesky Constitution that gives states power in times of crisis (not that FEMA was all that on-the-ball either). More of this is better?
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?
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