

Why are the cooling towers on nuclear power plants funny shaped? - hexagonal
http://www.howtospotapsychopath.com/2012/05/27/you-dont-want-to-meet-michael-palin-there/

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heeton
It's partially due to engineering practicalities too.

Take two rings (imagining they are the top and bottom of the tower) and tie
string vertically between them at 20 or so different points (these are the
long girders used to build the tower). You now have a straight cylinder.

Twist the top ring slightly, and all the 'girders' remain straight, but the
cylinder becomes a squashed hourglass, just like a cooling tower. This shape
is a lot stronger, but still uses plain straight girders.

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tobias3
I once went on a tour through a nuclear power plant and the cooling tower was
the one place where you could really get an idea of how much energy is being
produced there. You could feel the draft about 100m away and once you were
inside it was overpowering.

I mean we saw the turbines, power transformes the spent fuel pool and the
reactor hull and everything. But there you did not really get the right
impression, as opposed to standing inside a tower which produces clouds which
you can see from more than 50km away.

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martinkallstrom
tl;dr: It is called a hyperboloid shape and is very strong compared to other
curved surfaces because it can be built or supported by straight beams.
<http://en.wikipedia.org/wiki/Hyperboloid_structure>

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Retric
They are also surprisingly closely related to Tipi's.
<http://en.wikipedia.org/wiki/Tipi>

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jules
Hyperboloids can be made from straight tilted lines:
[http://upload.wikimedia.org/wikipedia/commons/a/ad/Ruled_hyp...](http://upload.wikimedia.org/wikipedia/commons/a/ad/Ruled_hyperboloid.jpg)

So tipi's _are_ hyperboloids with a small inner cross section.

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mrmagooey
I used to work at the stations mentioned, we had big signs on the nearby
highway pointing out that the "smoke" coming out of the towers was just water
vapour. The actual pollution was generally pretty hard to spot thanks to
various ash and particulate collection methods in action, that is unless one
of the boilers was being restarted and diesel was being burnt, in which case
the smoke was quite black and visible.

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nitrogen
OT: the div#dd_ajax_float element (the share buttons) on that page is really
annoying. Its fixed location and its style (e.g. it has a drop shadow, making
it seem to be physically closer than the content) make it seem 10x more
important than the content itself. I have to set it to display:none to read
the page.

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hexagonal
I never saw it. It must have been blocked by NoScript.

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daimyoyo
Minor point of clarification: the article says "pure steam...has no ceiling
temperature." Water vapor begins to decompose into oxygen and hydrogen around
2200C(1). Probably well above the threshold of anything capable of generating
electricity, but it does have a ceiling.

[http://en.wikipedia.org/wiki/Water_splitting#Thermal_decompo...](http://en.wikipedia.org/wiki/Water_splitting#Thermal_decomposition_of_water)

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dmlorenzetti
The BBC documentary linked at the end of this article, "Fred Dibnah,
Steeplejack", is right up the alley of many here on HN:
<http://www.youtube.com/watch?v=xuSW9kOBADo>

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Element_
That is a pretty crazy way to make a living. Here is a vid showing how they
setup the ladders on the side of the chimney.
<http://www.youtube.com/watch?v=F04dGK1_wYA>

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werpon
I always thought they were built that way to cool the air faster due to the
Jules-Thomson effect.

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puls
Upvoted for the hidden Wacky Waving Inflatable Arm-Flailing Tubeman link.

