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Old 2020-08-12, 10:00   #23
pinhodecarlos
 
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Originally Posted by Uncwilly View Post
There are wind energy capture designs that have the spinning bits on a vertical axis. One involves a capstan like structure the funnels wind from any angle upward through a robust bladed device that looks like a boat propeller. Another takes funnel that gets turned into the wind by a tail and also sends it vertical. These designs also the heavy weight of the generator to be at ground level.

The traditional farm Western windmill can handle high winds well.
False, there’s a limit, read about Betz’s law.
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Old 2020-08-12, 11:12   #24
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Thank you. I had been thinking about the same thing. It seems that ruggedness requirements might limit the size of turbines, but the high winds might make up for that in energy capture.

It's hard for me to imagine the design parameters for something that could survive and operate there.

How about a building-sized enclosure with intake shutters to direct/limit-as-needed the flow to internal dynamos? Here's some technical drawings as example (warning, google alert): Very, Technical
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Old 2020-08-12, 18:06   #25
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Quote:
Originally Posted by kladner View Post
It's hard for me to imagine the design parameters for something that could survive and operate there.
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Originally Posted by Uncwilly View Post
The traditional farm Western windmill can handle high winds well.
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Originally Posted by pinhodecarlos View Post
False, there’s a limit, read about Betz’s law.
My comments were addressing the survival bit, not the power generation at a high speed. Proper construction of a windmill on a derrick type tower as seen in "Old West" movies" is quite stout.
The other 2 designs I mention were designed to be hardy. The capstan style (which I can find a picture of at the moment) is very stout. And if the winds will be too strong, a shield can be rotated around from the leeward side to the windward side, to block the incoming air.
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Old 2020-08-12, 19:13   #26
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Originally Posted by kladner View Post
It's hard for me to imagine the design parameters for something that could survive and operate there.
I am sorry to break this to you but that is a failure of your imagination.

Some people are trying to work out how to run a useful rover on the surface of Venus (https://www.space.com/steampunk-venu...-nasa-jpl.html) without much in the way semiconductor electronics. Clockwork plays a big role. I proposed the use of thermal phase-change materials for an optical component in thenavigation and obstacle avoidance sub-system.
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Old 2020-10-22, 01:22   #27
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The toxicity is a worry, but site it downwind of human habitation, and toxicity is not of a "spill will despoil Antarctica forever" variety. Best part, NH3 is *solid* at std-atm-pressure and temps below -78C, so would only need very light pressurization to solidify it in storage tanks at typical antarctic temperatures. Thus the tanks would be much lighter and cheaper than those needed for compressed H2. The nitrogen to make the stuff is all around us, in air.
I did some thinking about this. At -50C at std pressure NH3 is a liquid. Based up the data here: https://www.pnas.org/content/99/12/7844 It looks like the temp of the ice just under the surface is in that range (I see a measurement of -48 at 810m down.) So, making a "tank" using equipment to dig out a hole and then lining it with suitable plastic (which can be welded on site to make it a single piece) would work. Rolls of plastic the width of the interior of a C-130 (or better a C-17, but they don't fly them there) would be manageable. Since the pole is a desert, there would not be much effort needed to keep the top clear of snow.
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Old 2020-10-22, 08:48   #28
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Since the pole is a desert, there would not be much effort needed to keep the top clear of snow.
Not in the usual sense. It's a continent size glacier system, sometimes called polar desert to distinguish it from true desert. You may be thinking of McMurdo, which is rocky, but that's on the coast, hundreds of miles away and near sea level. The snow/ice pack in the vicinity of South Pole Station is nearly 2 miles deep. There's not a bit of rock or sand to be seen there, unless someone brings it there. The Ice Cube project drilled holes 1.5 miles deep using a 4" diameter hose attached to a special drill head (basically a giant garden hose nozzle with steel ballast weights) spraying hot water to melt the way down, to around 0.5m diameter.http://www.psl.wisc.edu/projects/large/icecube https://en.wikipedia.org/wiki/IceCub...no_Observatory

The original station dome became inadequate partly because it is being buried by new snow and the work of digging out the entrances became too much.
The replacement shelter is designed for increases in elevation of the snow pack.
https://ferrarochoi.com/publications...tation-design/
They use large Caterpillar bulldozers to manage snow there and move equipment and cargo containers around. With a flat terrain that's all snow for many miles in all directions, drifting is an issue.

Indoors, at near room temperature, the relative humidity is mostly very low compared to outdoor, because the absolute humidity is same or similar, and the temperatures are very different. Anyone who needs RTV silicone to set goes to the kitchen where local humidity is higher because of the cooking.
Outdoor relative humidity is currently 46% at -51F. https://www.accuweather.com/en/aq/am...eather/2258520
Warm that air up to room temperature without changing water content, and you get 1% relative humidity. And that's their spring weather.

Elevation is 9301 feet, 9000 feet of which is snow and ice.
https://en.wikipedia.org/wiki/South_Pole

The local water supply is by drilling a hole somewhere and then melting out a roughly spherical cavern.

Amundsen's tent is thought to be buried 56 feet deep, implying a net accumulation rate of about 6"/year long term.

Last fiddled with by kriesel on 2020-10-22 at 09:12
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Old 2020-10-22, 13:48   #29
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Quote:
Originally Posted by kriesel View Post
Amundsen's tent is thought to be buried 56 feet deep, implying a net accumulation rate of about 6"/year long term.
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Since the pole is a desert, there would not be much effort needed to keep the top clear of snow.
Thank you for proving my point with your estimate.
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Old 2020-10-22, 16:41   #30
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Originally Posted by Uncwilly View Post
Thank you for proving my point with your estimate.
Unfortunately, the previous poster failed to emphasize the main problem:
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Originally Posted by kriesel View Post
With a flat terrain that's all snow for many miles in all directions, drifting is an issue.
It seems that drifting is the snow issue. The old station was buried under so much snow, it was ordered sealed because collapse was thought to be imminent.

Even the new, elevated structure, designed to control the drifting problem, is also designed to be raised a couple of times during its life, estimated at 25 years.
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Old 2020-10-22, 21:10   #31
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Even the new, elevated structure, designed to control the drifting problem, is also designed to be raised a couple of times during its life, estimated at 25 years.
It is not like it is in Buffalo, NY or Mt Rainier, WA.
The snow build up on a storage pond can be addressed. For example build snow walls in/on it and spray an ice layer of 10 cm to solidify and transfer any snow load. Add pipe lengths to the surface as needed.
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