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Cold weather is hostile, to most humans at least,
peoples have adapted well to extreme environments. In
there are people living far north of the arctic circle
the most enthusiastic of pizza menu delivery people dare
tread. Nevertheless, there are still
all but the most intrepid/daft humans. The depths of the
Antarctic continent have punishing low temperatures,
extreme winds, high altitudes, and formidable physical
such, people who find themselves there, tend to hunker
in research stations and apparently, drink an awful lot
winter. Nevertheless, there are people who dream of the
last remaining feats of exploration.
One such feat is a solo, unsupported transantarctic
trek*. This is particularly tricky. Since the antarctic is
high and undulating, you need quite a lot of equipment.
Significant clothing for insulation, additional sturdy tents
super thick sleeping bags, again for insulation. Fuel, to
water and cook food and then the actual food. Lots of
is the only real energy source for the person doing all the
and staying warm. This all has to be hauled along,
a sled. This is where the compromises creep in. You
can take less stuff, and move faster, but should you be
storm you may run out of resources waiting and be
complete the trek. Or, you can take a lot, and move
sapping morale and increasing the likelihood of
The energy needed to move is pretty invariant, humans
similarly efficient. What remains is the fuel for
and the energy required to keep warm. Now, people with
motivation than brains have discovered that a diet high
gets you a lot of dense calories, minimizing the excess
but we can do better.
There's quite a lot of research on how much heat people
cold environments, a reasonable example <link> suggests
-40C up to 20% of working and 30% of resting metabolism
expelled with normal breathing. That is a large amount.
is child's play compared to the temperatures and wind
modest 5 day antarctic storm can dish out.
So, we solve it. Breathing in cold air, heating it up and
humidifying it in the lungs and then breathing it out to
antarctic environment is a stupid waste of energy. So,
through a heat exchanger. This can be a super simple
Essentially a mouthpiece, a pair of counter current-
tubes and a little flappy valve or two. The best
be a central tube with a spiral arrangement around the
Breath in through one, out through the other with the
valve ensuring unidirectional flow. The system should
a couple of lungfuls of dead volume, this gives the air a
seconds to dwell and exchange temperature. Now, the
breath out will warm the air coming in. You save an
awful lot of
The by product is a bit of condensed water, this should
collected and may be drunk at (slightly disgusting)
Now, there is prior art <link> but this is just some
"stuff" that gets warmed during exhale and cooled during
Similar principle but nowhere near as efficient as a
exchanger. If they wanted to do a better job, the
be thin tubes containing a eutectic substance at an
temperature, although that would be difficult to get
depending upon conditions.
* When that's been conquered, it will be a solo
over the long axis, then in winter... until there are no
who will sponsor such increasingly tenuous connections
** fancy pants explorers with their fussy requirement for
separate fuel from their stove. Swap in the winter mix of
single battlefield fuel for extra efficiency.
Heat loss in cold temperatures
[bs0u0155, Feb 13 2017]
Heat exchange mask
[bs0u0155, Feb 13 2017]
Single Battlefield Fuel
Add extra glycerol for winter. [bs0u0155, Feb 13 2017]
I imagine it could be used for exhaled moisture as well. [2 fries shy of a happy meal, Feb 14 2017]
Dune [8th of 7, Feb 14 2017]
All those 5 day storms contain a huge amount of energy
[TIB, Feb 15 2017]
||I always thought the basic problem was low body mass, high surface area and having six spindly legs.
||//the Formicidae represent between 15-25% of the earth's biomass//
||That has to be wrong. That would mean that for every blade of grass, there's several ants. For every tree, a pile of ants extended to a fifth of its height. Definitely wrong.
||//leave trails of pheromones
||Well, the Soviet astronauts used pencils, so some scaled down version might help?
||// high altitudes and formidable physical barriers
||That seems to remind me of something...can't quite put my finger on it...
||// The by product is a bit of condensed water, this
should be collected and may be drunk at (slightly
||I think it is more likely to be ice!
||Not if you collect it at the point where it condenses
out but hasn't frozen yet.
||A reverse Stillsuit. Totally doable. [link]
||Actually, the clever thing would be to include sweat in
the loop. One of the most irritating tradeoffs with any
outdoors gear is how good a protective barrier it is vs
how much sweat builds up, we can solve that. When
breathing in, the outside air should go through the heat
exchanger, into the inner air space of the jacket and
then to be inhaled. This passes warm dry air over the
body, the body's sweat system will be in a good position
to regulate temperature and the inhaled air will be
humidified for free. The exhaled air should have the
humidity condensed to a liquid, stored to be drunk
along the way through something like a Lifestraw to
make it less horrid.
||Sonds like a Dune stillsuit.
||//Sonds like a Dune stillsuit.//
||Except mine will work. How is the stillsuit rejecting heat?
Sweat allows you to exist in temperatures above body
temperature by rejecting excess thermal energy into the
fairly robust enthalpy of vaporization. If they condense the
sweat in a desert, the energy isn't being lost. If you're in a
cold environment, none of that applies. The problem is a
huge excess of heat rejection, which gives you much more
wiggle room to manipulate the energy flow.
||Would they look like teletubbies without the tube and antenna ?
||See link. Renewable energy, even on a small scale should not
be discounted. Solar PV, thermal, wind could all generate a
fair amount of power without a lot of extra mass. Even linear
alternators could scavenge some energy from the ups and
downs of the sled. This energy could be stored in insulated
batteries or a phase change material like wax for later use.
Of course, a counterflow heat exchanger for breathing
sounds like it should already be standard equipment.
||//wind could all generate a fair amount of power //
||Plenty of people have done an awful lot of travelling
around the polar regions using kites. The consistent and
relatively predictable katabatic winds are useful for this
and combined with skis can really chew through the
miles. This is, of course, cheating. Arctic and antarctic
exploration is one of the many Endeavours, where the
British example should be the only example. For
example, you can ride a modified dirt bike to the pole,
you can fly there, you can have sturdy Russians drive a
large truck ahead of you setting up cabins. All cheating.
Being Norwegian: cheating. Keeping all body parts: