Why are nuclear cooling towers hyperboloid shaped?

[600burger]

Can someone point me to a website or book that explains why nuclear cooling stacks are shaped the way they are? (i.e. hyperboloid)

-Burg

 

[z4955]

I did a quick search and came up with this site:

http://www.google.com/search?hl=en&lr=&q=nuclear+cooling+tower+shape

 

[hitssquad]

Cooling towers are for plants that use steam turbines. They don't have to use them. When they are used, less hot water is released to the local water system. Not all steam-turbine-driving nuclear power plants use cooling towers. Some coal plants use cooling towers.
images.google.com/images?q=coal%20%22cooling%20tower%22

 

[hypatia]

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