Why does Carnot's name appear on so many concepts and formulas?

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Why do so many ideas have Carnot's name on them?

Carnot did What?

Which of these were authored, discovered or invented by Sadi Carnot?

  1. Carnot Cycle
  2. Carnot Ratio
  3. Carnot Efficiency
  4. Carnot Theorems (1 and 2)
  5. Carnot Limit
  6. All of the above

Sorry. Trick question. The answer is "a."the Carnot cycle.

Everybody wants to tag their ideas with Carnot

The Carnot Ratio AKA the Work Ratio was authored by a contemporary of Sadi Carnot and Lord Kelvin. He is mentioned in their book (more on next page).

The "Carnot Efficiency", is 1) a misnomer of Carnot Ratio or work ratio and/or 2) a misunderstanding of the work-work ratio of the Carnot Cycle coupled with a misunderstanding that the Carnot cycle is uniquely reversible and optimal. The idea being, if the work ratio is a percentage of heat converted to work, well that must be the engines efficiency. Counter examples coming, including a loss-less engine. Read on.

Carnot Theorems 1 and 2 are actually misquotes of Lord Kelvin's theorem in the shared publication,"Reflections", page 161-162. The also demonstrate their lack of understanding of Lord Kelvin's theorem. If anything, they should be Kelvin Theorems 1 and 2, and they really should have got the point correct, but they have the opposite point. (Kelvin's theorem says all vapor engines get all the work possible from heat consumed during expansion. So how can engines behave with different efficiencies? The thermodynamic conversions between heat and work are identical in all engines. Engines only differ in how much they leak heat, leak vapor, and leak work.)

The Carnot Limit is the idea that since observed machines get lower efficiencies than the Carnot Ratio or Work Ratio, then the Work Ratio must be some abstract ideal, and real machines do less than the ideal. Actually the Work ratio is cast in Stone, a measurement of Work Produced by Newton's laws of motion. Force times distance, or the equivalent, Pressure times Volume. All air/vapor/steam/gaseous state matter behaves exactly the same in all machines. The real Kelvin theorem is just that, there is only one rate of energy exchange between heat and work, and that is 100%.

That the authors had this insight and others equally profound, prior to the formulation of the law of conservation of energy, speaks volumes about both Carnot and Kelvin. They also both independently stated a belief in the principles of Conservation of Energy years before Clausius formalized it as The Fundamental Principle of Thermodynamics. Are they rolling in their graves because they spelled it out for us mere mortal's and we still got it wrong 200 years later?