Carnot cycle explained!

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Lopez Mike
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Carnot cycle explained!

Post by Lopez Mike » Thu Oct 25, 2018 3:11 pm

At last, an explanation of the Carnot cycle that I can understand.

HTTPS://XKCD.COM/2063/

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Re: Carnot cycle explained!

Post by steamboatjack » Fri Oct 26, 2018 7:57 am

I used to have a Carnot cycle but the wheels fell off!
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Re: Carnot cycle explained!

Post by RGSP » Fri Oct 26, 2018 12:23 pm

steamboatjack wrote:
Fri Oct 26, 2018 7:57 am
I used to have a Carnot cycle but the wheels fell off!
Jack
That must have been Fred Carnot's.
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Re: Carnot cycle explained!

Post by TriangleTom » Fri Oct 26, 2018 1:04 pm

steamboatjack wrote:
Fri Oct 26, 2018 7:57 am
I used to have a Carnot cycle but the wheels fell off!
Jack
Hence the name, Car?Not! cycle.
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Re: Carnot cycle explained!

Post by RGSP » Fri Oct 26, 2018 2:48 pm

To be fair, my undergraduate degree did include significant thermodynamics, and I spent many hours doing things with entropy-enthalpy diagrams for both water and refrigerant 12. Once you understand those fairly well, the different thermodynamic cycles sort of fall into place reasonably neatly. The trouble is there is significant cylinder wall condensation and/or heat loss in our little engines, to say nothing of heat losses in the pipework and valve gear, so the perfect theoretical cycles are helpful, but only as a general guide. The number of really good, well educated, engineers ever involved with designing and building steam piston engines was tiny, and, all things considered, the best of the rest (a large number) did pretty well from experience and waving wet fingers around!

I also remembered that Fred Carnot spelled his name Karno, but given his talent for apparent incompetence, maybe the former is OK.

Incidentally, a lot of people recognise the word "entropy", even if few can define it; I wonder how many can do the same for "enthalpy".
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Re: Carnot cycle explained!

Post by wsmcycle » Thu Feb 07, 2019 10:48 pm

I really, really liked the Isopropyl phase. I had often wondered.
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