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Carnot to be Revised

I am scribbling furiously, there's a reason why I used such unusual approach. Will post within the next few days, meantime, here's the source of the data that I will use:

Source of data: NBS/NRC Steam Tables by Lester Haar, John S. Gallagher and George S. Kell; publisher: Hemisphere Publishing Corp.; part of NSRDS (National Standard Reference Data System, USA). The tables are the result of research work by IAPS.

I will refer to two Rankine cycles, so as to compare like with like, difficult to include diagrams in here (google/Yahoo), however, the diagrams referred to will Ps diagrams. The usual squares/rectangles where the vertical = pressure and the horizontal = entropy.

Thanks and regards Dietmar

Reply to
DFD
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Again, we eagerly await your conclusive results. Proving Carnot wrong would most definitely be newsworthy and open the world up to some rather interesting possibilities. We are quite familiar with the steam tables, so it is a great place to prove your point. At this point we aren't too concerned with how you do it, as long as the data is used correctly and your observations are valid.

Michael

Reply to
Herman Family

This is definitely not true. Carnot defined the maximum efficiency that can be achieved with an ideal reversible heat engine. This efficiency is still less than 100%. A perpetual motion machine would require at least 100% efficiency to work.

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Reply to
charliew2

OK, I should have said "Perpetual motion machine of the second kind", but I figured the distinction would probably have been lost on the originator of this thread.

A perpetual motion machine of the first kind creates energy out of nothing. One of the second kind can tranfer heat from a cold reservoir to a hot reservoir: ie violates the Clausius statment of the second law: "It is impossible to construct a device which operates in a cycle and produces no other effect than the transfer of heat from a cooler body to a hotter body". (Such a machine could eg power a ship by extracting energy from the ocean leaving behind chunks of ice, the energy so gained being used to propel the boat. It is certainly a kind of perpetual motion machine even though no energy is being created or destroyed.) Talking about the "efficiency" of a perpetual motion machine of this kind is meaningless.

The Carnot efficiency is a consequence of this formulation of the second law.

Reply to
Coriander Lexus

I'm pretty sure most reputable physicists would say that the zero-point field is real, but rather difficult (and perhaps impossible) to manipulate.

Regarding the original post -- were I a betting man, I'd go with Carnot. (No offense to DFD intended.)

jim andrews

Reply to
jim andrews

I dunno, Utah?

jim andrews

Reply to
jim andrews

Somehow in the recesses of my deteriorating memory, I seem to remember one of them relocating to Michigan. The other, maybe still in Utah? Both are no longer with the university, though, I think. At least one tried, or is trying, to make cold fusion a commercial success somehow.

Bob

Reply to
Robert Kim

Oops, I stand corrected. They got a little further than Michigan. Told you my memory was going.

***** Quote from
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"Other cold fusion researchers were likewise reviled - especially Pons and Fleischmann, who eventually retreated to the south of France, where Pons adopted French citizenship."
Reply to
Robert Kim

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