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Anti-Frostidigitation: Heatpipe Gloves
Hettinga writes "A little casemod couture this morning, courtesy of Hongbin Ma, a professor of Mechanical and Aerospace Engineering at the University of Missouri. He has developed heatpipe-driven gloves which pump therms from your toasty upper arm down to those aforementioned frosty digits. 'Each glove contains five small heat pipes, one for each finger, that are about 14 inches long and 1 mm x 2 mm in the cross section. Each pipe consists of three sections: an evaporating section, which is attached to the upper arm area; an adiabatic section, which is between the finger area and the arm area; and the condensing section, which is attached to the finger area.' Coming soon to a half-pipe near you..."
Too bad nature decides to shut it off in the hands when it gets cold.
I can't imagine that little bit of lost heat was the difference between life and death for anyone. But, the fact that we have evolved the feature suggests it was.
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There are those with poor circulation in the extremities whose bodies have some trouble warming hands and feet back up once they've gotten cold. Speaking as one of them, once my feet have gone cold, they stay that way for ages, even after getting into a warm (or even hot) envinronment, changing shoes/socks for warmer/dryer pairs, etc.
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It's actually better to keep your torso warm.
The draining of blood and heat from your hands and feet happens when your core temperature starts dropping. This is done to protect the vital organs, heart, liver etc over the non-vital, hands, feet. If you can keep your core temperature normal you can actually work without gloves even below zero (celsius). This because the body is warm and needn't cut the heatloss from hands or feet.
There was a good documentary on the Discovery channel about the very subject not long ago.
So, while heatpumping gloves seem nice, I'd go with keeping my body warm and be rid of any gloves hindering my hands.
Yeah, bring on the puns..
This is short circuiting nature, basically as we get cold extremities like the hands and fingers have the blood circulation restricted to conserve heat so our core body temp stays high. Fingers are far more robust in surviving cold than say our brains, they are also more expendable, and they also have a larger surface area to mass ratio so are costly to keep at body temperature anyway.
What it really means is that the garment that this is in is less thermally efficient than the same garment without (you will lose heat faster). It maybe handy for delicate work were you need thin gloves and warm hands in a cold environment with the only other real option is an active heating system power by batteries.
I can't imagine that little bit of lost heat was the difference between life and death for anyone
Let's say you don't have the option of going somewhere warm (ie, inside to a nice toasty fire)... Which do you have a more critical (ie, life-preserving) need for - To keep using your large muscles (legs, upper arms), which serves both the purpose of generating heat and might eventually move you to somewhere warmer; or, manual dexterity, which would only really help if you needed to operate a book of matches (something that didn't exist for 99.99999% of human history)?
Our bodies decrease blood flow to the extremities for precisely that reason. Additionally, assuming the worst, we can live without a few fingers or toes or even an earlobe; Sacrificing them to keep our core body temperature high enough seems like a viable tradeoff under extreme circumstances. The fact that we now have thinsulate and heat-packs and almost always a warm place to go nearby, so having our fingers nice and toasty seems more useful than preventing the small heat loss from them, had no effect on how we evolved.
But, the fact that we have evolved the feature suggests it was.
Although this may seem in direct contradiction to my point above, I mention it only for clarity... Not all inherited traits "evolved" in the natural-selection sense. One of the fundamental ideas behind evolution says that mutations occur essentially at random, and those that increase our odds of reproducing (which dying young does not) get passed on. However, those traits that have no effect whatsoever on our chances of reproducing can also get passed on, just by blind chance. For a trivial example, Alzheimer's disease - It doesn't affect people until they've passed their reproductive prime, so as debilitating as it seems in later life, it doesn't reduce its own chances of remaining in the population.
I think this is a problem of human evolution versus current technology. Currently a person can buy a coat to keep their core nice and toasty, but extremeties (hands, feet, ears) are much more sucessptible to the elements. In this case the device is pulling heat away from an area that is easily insulated, to heat an area that is difficult to insulate.
Additionally this could be very handy for jobs that require people to be outdoors, yet use their hands. In the recent cold spell here in New England, I felt terrible for the toll collectors, construction workers, and police who could bundle up, but still couldn't wear heavy heavy gloves since they needed to use their hands. This technology would allow for a very light weight set of gloves that would allow mobility of the hands, while insulating the rest of the body as mush as needed.