How does this thinkgeek air conditioning device work?

I was wondering, how does this device work? http://www.thinkgeek.com/gadgets/travel-outdoors/c400/ I tried to understand it, but if it does work filtering water, wouldn't the water have to steal heat from the device, and than the vapor would be blowed to my face, giving it heat to return to liquid state?

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frollard7 years ago
"Evaporative cooling is the trick here. Simply drizzle a few ounces of water onto a sponge, and place it in a device a little bigger than a cordless phone, and enjoy cool breezes wherever you go. The fan draws air over the damp sponge, cooling it by up to 25 degrees Fahrenheit."

Quoted from the site you linked.

Evaporate = lose heat = get colder.

Your skin isn't cold enough to cause the water to re-condense so it wouldn't condense - so you would get cold, humid air blown at you.

It works best when the air is dry and can hold more relative humidity. This 'swamp cooling' won't work on a muggy day because no water evaporates into the near-saturated air, so no evaporative cooling takes place.
kelseymh7 years ago
Ro]x[as7 years ago
The water is absorbing heat from the air passing through it and evaporating, cooling the air. The air coming out is going to have some water vapour in it, but I don't think there's going to be enough from a sponge to have a lot of water condensing on your face. For the vapour to condense onto your face, your face would have to absorb heat from it. The speed of the air passing over your skin, and the fact that your skin is probably relatively hot means that heat is going to go the other way; from your face into the air passing over it.
Re-design7 years ago
It's a hand held swamp cooler. Water is poured over a loose weave filter and air is sucked or blown thru the filter and by the magic of evaporation the temperature is lowered and you feel cooler. Works that same as when you sweat and the breeze evaporates the sweat and you feel cooler.