There is a fundamental fracture in "reality".
A break between the Caloric and Kinetic idea or theory of heat engine operation which thermodynamics generally attempts to reconcile, apparently without ever recognizing or acknowledging that any conflict or contradiction even exists.
Carnot stated flatly and unequivocally"
The production of motive power is then due in steam engines not to actual consumption of the caloric but to its transportation from a warm body to a cold body.
The pure, or original "Carnot engine" or cycle made no provision or allowance whatsoever for any interconversion of heat into work or work into heat.
Yet, in the thermodynamic literature generally, Carnot's statement, quoted above, is reaffirmed as if it were actually true, cited without qualification or comment or the falsity of the statement is altered or glossed over by inserting the word "some": "some heat is converted to work" as if that somehow resolves the contradiction and makes everything OK.
Some examples:
Bright Hub Engineering
The Laws of Thermodynamics Were Discovered by Sadi Carnot
Discussions on Ideal Engine
...
The engine working on Carnot cycle is the most efficient engine because in this engine there is no friction at and no exhaust gases are emitted. In the ideal engine there is no conduction of heat between different parts of the engine, which are at different temperatures....
He also made it clear that the maximum efficiency of the engine was dependent not the type of fluid used by the engine, but on the temperatures between which the engine is operating, which he considered the motive power of heat.
Path breaking findings for the Second Law of Thermodynamics
With these discoveries Carnot made two conclusions:
1. The production of motive power is then due in steam engines not to actual consumption of the caloric but to its transportation from a warm body to a cold body.
2. In the fall of caloric the motive power evidently increases with the difference of temperature between the warm and cold bodies, but we do not know whether it is proportional to this difference.
These findings were the foundation for the second law of thermodynamics, which states that the natural tendency of heat is to flow from high temperature reservoir to low temperature reservoir.
https://www.brighthubengineering.com/th ... art-three/
In reading these passages, no indication is given that Carnot's statement is anything less than a foundational axiom, discovery or "finding"
In the Caloric, or in Carnot's world view, "Motive power" or "work" is conceived to be the result of heat being "transported" by the working fluid so that none is lost in the process. There is no "consumption" of heat for the output of useful work.
This is the naive conclusion reached by Carnot's water wheel observations.
Water goes into a bucket at the top of the water wheel and ALL of the water is let out at the bottom. Work is accomplished but no "fluid" is lost or "consumed" or converted. The heat just runs in from the "high reservoir" on the hot side of the engine and runs out into the "low reservoir" on the cold side.
If heat were actually some kind of fluid, the fact that this contradicts observable reality and is a violation of conservation of energy might be avoided somehow, but if heat is recognized to be a form of energy, then we have a problem.
If heat is energy, and work is another form of energy how can the heat flow through the engine from the hot to the cold "reservoir", like water through a waterwheel, producing work output in the process? You would have the production of energy as "work" out of nothing, or heat energy being used to create more energy.
This conundrum is routinely passed over, treated lightly or just ignored. Quite often it is treated as a kind of wonderful miracle.
This simplest heat engine is called the Carnot engine, for which one complete heating/cooling, expanding/contracting cycle back to the original gas volume and temperature is a Carnot cycle, named after Sadi Carnot who in 1820 derived the correct formula for the maximum possible efficiency of such a heat engine in terms of the maximum and minimum gas temperatures during the cycle.
Carnot's result was that if the maximum hot temperature reached by the gas is TH,
and the coldest temperature during the cycle is TC,
(degrees kelvin, or rather just kelvin, of course) the fraction of heat energy input that comes out as mechanical work , called the efficiency, is
Efficiency = TH−TC/TH.
This was an amazing result, because it was exactly correct, despite being based on a complete misunderstanding of the nature of heat!
https://galileo.phys.virginia.edu/class ... Engine.htm
Wow! "exactly correct"!
I've strained to discover when, where or by whomever, or by what method or means this was actually verified to be "exactly correct".
Here we can find a brief discussion on a physics forum:
https://www.physicsforums.com/threads/d ... ry.650289/
Reference is made to "Truesdell's 'The Tragicomical History of Thermodynamics 1822-1854'.
Andy Resnick said:
The most complete source for information like this is Truesdell's "The Tragicomical History of Thermodynamics 1822-1854". To summarize: Laplace invented the caloric theory: heat is never created or destroyed. Carnot did indeed use this theory, for example when he wrote "Thus the production of motive power is due... not to any real consumption of caloric, but to its transport from a warm body to a cold body..." However, Carnot's result- the analysis of a cyclic process- does not make use of caloric theory. As Truesdell writes: "The spectators ... will see that the protagonist while seeming to smelt lead has cast a gold ingot."
Needless to say, I don't personally find such arguments, that somehow Carnot pulled off some kind of miracle convincing or "scientific" in the least, but that seems to be about as much in the way of proof ever offered.
Carnot somehow pulled a rabbit out of a hat and came up with the right answer, in spite of being wrong. That his theory contradicts conservation of energy is just glossed over and ignored.
In the carnot cycle/engine, heat is absorbed by the working fluid effecting a state change. The gas expands in volume without a drop in temperature, as the usual drop in temperature that would normally result from expansion is compensated for by the absorption of heat.
Subsequently that heat is transfered to the cold "reservoir" and the gas is "compressed". There is no elevation in temperature that would normally be associated with compression because this heat is taken away by the cold "reservoir".
In short, the heat is
transported
This process is completely "reversible". Like turning a water wheel backwards, water can be lifted up again!
But it is apparently imagined that some kind of "efficient" conversion of heat into work takes place in this device through this process of taking in heat and letting it out again. Somehow this is believed the "most efficient engine possible". An engine that simply takes in a quantity of heat and let's it out again, without any reduction of that heat. What goes in must come out, AND we also have the greatest possible production of useful work output to boot!
It was observed however that in a REAL engine, not all the heat came back out. The numbers didn't add up.
How to account for the missing heat? Why did some of the heat seem to vanish?
Was it recognized that "some" heat was actually being
converted to WORK?
Apparently not. The heat was being lost to "ENTROPY".
Is any of this rational? I am hard pressed to find any logical consistency in all this. These ivory tower conclusions reached about "ideal" engine cycles have no real world correspondence.
You may as well say that no horse can run as fast as a unicorn as to say no engine is more efficient than a Carnot engine.