“We want to put water right into your processor.” If that statement makes you sweat, that is good. Sweating is what we’re talking about, but it’s more involved than adding some water like a potted plant. Sweating works naturally by allowing liquid to evaporate, and that phase change is endothermic which is why it feels cool. Evaporative coolers that work in this way, also known as swamp coolers, haven’t been put into computers before because they are full of sloshy water. Researchers in South Korea and the United States of America have been working on an evaporative cooling system mimicking the way some insects keep themselves cool by breathing through their exoskeletons while living in damp soil.
Springtails are little bugs that have to keep the water and air separate, so they don’t drown in the wet dirt where they live. Mother Nature’s solution was for them to evolve to do this with columns that have sharp edges at the exit. Imagine you slowly add water to a test tube, it won’t spill as soon as you reach the top, it will form a dome. This is the meniscus. At a large scale, say a river dam, as soon as you get over the dam you would expect spillage, but at the test tube level you can see a curve. At the scale of the springtail, exuded water will form a globe and resist water pressure. That resistance to water pressure allows this type of water cooling to self-regulate. Those globes provide a lot of surface area, and as they evaporate, they allow more water to replenish the globe. Of course, excessive pressure will turn them into the smallest squirt guns.
We have invented a lot by copying Mother Nature. Velcro was inspired by burrs, and some of our most clever robots copy insects. We can also be jerks about it.
This quick and easy evaporative cooler might be just the thing the next time the air conditioning goes on the fritz. [Stephen] saw an eBay listing for a personal air conditioner that used a moist sponge and fan to send some cool relief your way. But he wanted to run his own test to see if it really did anything before laying down the cash.
The idea is to run air past a moisture source. Some of the heat energy in the air is reduced through evaporation resulting in the exhaust air feeling a bit cooler. It’s the same concept used in swamp coolers (an evaporative type of air conditioning). To build his device [Stephen] grabbed a refrigerator deodorizer which uses a hinged plastic cage to hold a packet of baking soda. He attached a small PC fan to the cage, then inserted a damp sponge. This is so easy to put together you could hit the dollar store on your lunch break and have some relief for the second half of the work day.
If you’re looking for a technique that cools just a bit better consider leveraging a beer fridge as a personal cooler.
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Producing ice without electricity just got a lot easier thanks to these engineering students from San Jose State University. Their system uses solar heat to facilitate evaporation of a coolant. When the sun goes down and the coolant turns back to liquid, its temperature drops drastically due to extreme pressure differences. The unit can produce 14 pounds of ice per day with zero carbon footprint. It has no moving parts and an entirely sealed system, this should mean that the only maintenance necessary would be keeping the unit clean.