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Keeping our troops in Iraq cool in the 104 degree weather Answered

Any idea's of keeping our troops cool in Iraq? Temperature rises to 100's during the day. Seems our government only has more cumbersome vests with (the lightest) cooling motors of 6 pounds and from what I gather can only be used in a vehicle.

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gyromild (author)2007-08-25

I love this ible Hilsch Vortex Tube

And i think combining a miniature Hilsch vortex tube, with rubber air-sac inside the soles of soldier's boot could possibly work. The compressed air is generated by soldier's bodyweight pressing on the air-sac while walking.

The question is how effective is the tube if it has to rely on such a small source of pressurized air..

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NachoMahma (author)gyromild2007-08-25

. It takes a lot of air to run a vortex cooler; much more than a "boot pump" will put out. As per the iBle - "(make sure you're running the tank around 100-150 PSI)" - it takes quite a bit of pressure, too. . They are real handy when you have a good source of compressed air (eg, under a sandblasting suit) or in areas where electricity is too dangerous.

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Weissensteinburg (author)2007-08-24

On a more serious note, would it work to have a hollow necklace, filled with some kind of refrigerant, and a camelbak style pack to convert the gas to liquid and back? Would that be too expensive? Too big? Too heavy?

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. It would work, but has a few problems. . All materials that I know of that would work (Freon, ammonia, CO2, N2, etc) are asphyxiants, so having it that close to the nose/mouth is not a good idea. Although the neck (and head) should be a very good place to remove heat; plenty of blood flow. . Any gas/liquid conversion system will take a lot of power, ie, weight, to run. . Noise reduction would not be insurmountable, but would add weight. . . It would probably be a valuable piece of gear on certain missions (when you could leave something else behind), but I don't think it would work for a battlefield soldier. . There are a lot of good systems out there (including your "necklace") that work well in special applications (usually where "low cost" power is available). An astronaut or pilot does not have to worry as much about carrying around an extra 20 pounds of mass as a foot soldier.

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trebuchet03 (author)2007-08-24

The best way would be to relocate them... To say their respective hometowns ;)

Fan + Helmet Like this storm trooper helmet - Make is solar powered and we'd have a green army o.0

So, an astronaut's space suit uses water, a pump, an undergarment with flexible hose, batteries and liquid oxygen (needed for breathing anyway). Of course, this makes one less mobile. But that's one solution and as mentioned, there are alternative gases.

So then there's systems like this. But again, heavy, bulky, limits mobility.

Really, the big problem is the large size of a suitable heat exchanger. Even when you do a liquid--gas phase change, the equipment is too bulky. If you've ever seen a photograph of an astronaut or cosmonaut carrying a box connected to their suit (on earth) -- that's the heat exchanger -- that's what holds the liquid gas :/

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NachoMahma (author)trebuchet032007-08-24

> the equipment is too bulky . At our current level of technology, that pretty well sums it up. Maybe "someday." Not sure there is _any_ way to get the size of the heat exchanger down - one can only get rid of so much heat when the ambient temp is 104degF. What would that make the deltaT - 20degF? 25? . How many Watts (or other units) does a person put out as body heat? My search skills don't seem to up to the task. I've seen some figures before, but no idea where. . . When I first saw the Storm Trooper helmet, I had to laugh, but then realized a mil-spec version of that would probably be pretty effective. Some very efficient motor/fan designs and compact batteries available nowadays.

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trebuchet03 (author)NachoMahma2007-08-24

Yes, there's always the someday scenario -- but hopefully, someday we won't have the need to cool off troops in Iraq :/

This seems to be a decent source for heat output.

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Weissensteinburg (author)2007-08-24

Ice Cubes!!!!! Lots and Lots of Ice Cubes!!!!

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jtobako (author)2007-08-21

Small canisters of liquid CO2 or nitrogen slowly releasing cold gas threw vents in their armor. Even if the gas temp is not cold, the dryness of it should help evaporate sweat.

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NachoMahma (author)jtobako2007-08-22

. What about suffocation in an enclosed space? . You'll probably use 10 lb/hr of liquid or more (just guessing - anybody have an accurate figure?). That's a lot of weight to be toting around. . If you get shot through the cannister, you have a bullet wound AND frostbite.

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jtobako (author)Firebert0102007-08-24

You mean like a pop can explodes?

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jtobako (author)NachoMahma2007-08-22

1) stick to nitrogen (co2 was mentioned because of low cost, but liquid n2-with the right equipment-might be cheaper). 2) A propane cylinder (20 lb) takes several hours to get cold enough to freeze up (get cold enough to stop evaporating-usually with a thick coating of frost on it). N2 and co2 should be more efficient with lower boiling points. Somewhere, I have tables for hole size/pressure/cubic feet per second comparisons (for propane), but I have no idea how many cubic feet of air you would need to move in order to convert to lb/hour. 3) N2 and co2 have evaporate very quickly at 1 atm-a small amount of padding or placing it outside of the armor would prevent most problems. The necessary insulation and heating (preferably body heat) needed could be designed to absorb any leaks. It's an idea, needs work (a venturi system could increase the volume of air for cooling, but tends to be noisy-not something you want on patrol).

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lemonie (author)2007-08-23

And as a second comment: "Any ideas about keeping our troops alive in I-raq?"

L

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lemonie (author)2007-08-23

Didn't they fit air-con to the vehicles? In real terms, you need to do as the locals do (though that might not make you bullet-proof) L

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canida (author)2007-08-21

For basics, have you seen this neck cooler? Not a high-tech solution, but a decent aid in the short term.

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NachoMahma (author)2007-08-20

. That's a tough one, especially for personal cooling gear. . First off, it must be small, light, and flexible enough that it will not impede the soldier in battle. And it must perform well enough to be worth toting the weight around. . I forget how much heat a person puts out when exercising, but it was pretty high. Making something that works, and meets the first criteria, will be difficult. The power source alone will be pretty heavy (which may be why they only work in vehicles). . Not trying to discourage you - it's a great idea - but I don't think it will be easy. A damp headband and a little shade does wonders, but shade can be hard to find in the desert. . . For cooling groups, evaporative cooling should help, but will require a lot of water. No matter what you do, you have to haul a lot of mass around.

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