Stirlingengineforum.com

I can "prove" my claim.

8+8=16

16/2=8

Let Tls = Tom's left shoulder
Let Trs = Tom's right shoulder

Tls + Trs should add up to 16

Just look at the numbers!

Tom Booth wrote: ↑Sat Apr 20, 2024 10:25 pm

Fool wrote: ↑Sat Apr 20, 2024 1:41 pm ...
I'm on Matt's side. Gas never contracts.

.... Gas doesn't ever pull. ...

I don't think "pulling" is often included in a definition of "contract".

Some definitions from some online dictionaries:

to cause to draw more closely together

to reduce to smaller size by or as if by squeezing or forcing together.

Gases have attractive forces and when cooled or brought closer together by being compressed, the attractive forces get stronger and this can moderate or ebate the pressure.

Think of it like pushing or "compressing" magnets closer and closer together. You will need to put pressure on the magnets with your fingers to push them closer and closer, but as they begin to attract each other the pressure on your fingers will grow less and less and it will be easier, or take less force to push them together.

Likewise when gases are compressed in a cylinder eventually the gas molecules start attracting and the gas will become easier to compress, and the pressure will begin to reduce as the gas molecules get closer and closer and the attractive forces begin to dominate.

Eventually, the attractive forces will cause the gas to liquify, but even before liquefaction, the pressure will start to reduce and the gas will become easier to compress.

You won't generally hear or read about this in courses on the ideal gas law or the kinetic theory, as these teach what is essentially a falsehood that gas molecules "never" contract and never attract each other but move freely never interacting at all.

Why such false and misleading information is so prevalent and allowed to proliferate in our educational institutions is difficult to fathom.

compression_increases_attraction.jpg

Attractive force is different for different gases:

https://chem.libretexts.org/Ancillary_M ... Real_Gases

https://chem.libretexts.org/Bookshelves ... lar_Forces

Cooling or compressing a gas causes the gas molecules to attract each other more and more.

The more the gas molecules are attracted to each other due to cooling or being compressed, the attractive force offsets the pressure so the pressure on the container is less.

At first you need to put pressure on the magnets to push them towards each other, but eventually they begin to attract each other more and more until the pressure on your fingers lessens and then goes away completely as the magnets snap together. But the magnets always had some attractive force. It just gets much stronger as they are brought closer together.

In the same, or a similar way, gas particles attract each other. The more their "kinetic energy" is reduced, that is; the more they are cooled or the more they are compressed (or both) the more the attractive force increases. Eventually if the molecules get close enough and the attractive force dominates the gas will liquify.

But even before liquefaction, like the magnets, the mutual attractive forces is ALWAYS present, it is just overcome by the repulsive forces at high temperature and low pressure. But as the temperature is reduced or the gas is forced to occupy a smaller area the attractive force increases and the gas contracts.

Think of it like pushing or "compressing" magnets closer and closer together. You will need to put pressure on the magnets with your fingers to push them closer and closer, but as they begin to attract each other the pressure on your fingers will grow less and less and it will be easier, or take less force to push them together.

What way? I don't think I said anything about how magnets work.

Oh yes you did.

Besides :

When two plus two equals twenty two.

One plus one equals two too.

Unless it equals 10.

Molecular attractive force isn't changed by temperature. Temperature is only equivalent to velocity.

Fool wrote: ↑Mon Apr 22, 2024 6:30 pm Molecular attractive force isn't changed by temperature. Temperature is only equivalent to velocity.

Nobody said temperature "changes" attractive force. Quite the opposite, I said the molecular forces are always there, just as magnetic force is always there. Cooling reduces the "repelling" forces that counteract the attractive force. That is, more "kinetic energy" keeps the molecules apart. Forcing the molecules closer together will bring them within range so the attraction is "felt" more.

Anyway, I described that magnets attract and what happens when they are pushed together, not "how" they "work". How or why magnets attract wasn't the topic.

Anyway, what about my description of the behavior of magnets do you not agree with?

You don't think they attract more or stronger when closer together or what?

You don't think the force required to push magnets towards each other diminishes as they get close enough to attract?

Maybe you've never played around with magnets much.

I think it goes without saying the poles need to be turned the right way.

Tom Booth wrote: ↑Sun Apr 14, 2024 7:18 am Nobody could build a Carnot engine so how could you ever "prove" it isn't "the most efficient engine possible".

Well, after some thought, my reasoning was, If heat is, or isn't supposed to go through the engine and is or is not "converted" and all this is too difficult to trace or something, and you can't build a Carnot engine for comparison, we do at least have real engines and you should at least be able to catch the "rejected" heat leaving the engine on the "cold" side of a REAL engine and work backwards from there. How much heat does a Stirling engine actually "exhaust"?

The answer to this question is clearly "nearly all of it". That's why we get so few Watts of useful mechanical power out of our Stirling engines compared to the energy in the huge quantity of combusted gases we hurl at the hot side of the system.

And the heat isn't just leaving the cold side of the system. Everything radiates according to its temperature, in all directions. There's half your propane gone already. Its combustion heat never got transferred into the working fluid because it radiated back into the surrounding environment from the outside of the hot cap. That's your max efficiency down to 50%, regardless of whether Carnot is a dead dog or not.

Then ther'es the acoustic energy losses, or in less technical parlance, clanking...

Stroller wrote: ↑Mon Apr 22, 2024 11:01 pm

Tom Booth wrote: ↑Sun Apr 14, 2024 7:18 am Nobody could build a Carnot engine so how could you ever "prove" it isn't "the most efficient engine possible".

Well, after some thought, my reasoning was, If heat is, or isn't supposed to go through the engine and is or is not "converted" and all this is too difficult to trace or something, and you can't build a Carnot engine for comparison, we do at least have real engines and you should at least be able to catch the "rejected" heat leaving the engine on the "cold" side of a REAL engine and work backwards from there. How much heat does a Stirling engine actually "exhaust"?

The answer to this question is clearly "nearly all of it". That's why we get so few Watts of useful mechanical power out of our Stirling engines compared to the energy in the huge quantity of combusted gases we hurl at the hot side of the system.

And the heat isn't just leaving the cold side of the system. Everything radiates according to its temperature, in all directions. There's half your propane gone already. Its combustion heat never got transferred into the working fluid because it radiated back into the surrounding environment from the outside of the hot cap. That's your max efficiency down to 50%, regardless of whether Carnot is a dead dog or not.

Then ther'es the acoustic energy losses, or in less technical parlance, clanking...

I agree with the highlighted text.

I've said the same thing, and have asked if "rejection" in the Carnot limit applies to such heat that "never got transfered into the working fluid"..

For example, suppose an electric heating element is put inside the engine and the "hot side" is insulated with refractory, silica aerogel + vacuum, + infrared reflective gold lined whatever, so any heat escaping is negligible. Do we then include the waste heat from the coal burned at the electrical power plant? Or what is meant by "rejected" to the "cold reservoir".

Scientific terms should have well defined understandable terminology. What exactly "rejected" heat includes depends on who you ask.

Does it include heat that never entered the engine at all? If so, the "Carnot Limit" is meaningless, as that is a wild variable. In a solar heated Stirling, maybe that includes the entire heat output of the Sun, which, as you say: "radiates according to its temperature, in all directions".

Carnot, the presumed author of this arguably ambiguous terminology wrote pretty non-ambuguously:

The production of motive power is then due... not to an actual consumption of caloric, but to its transportation from a warm body to a cold body

And

According to established principles at the present time, we can compare with sufficient accuracy the motive power of heat to that of a waterfall. Each has a maximum that we cannot exceed, whatever may be, on the one hand, the machine which is acted upon by the water, and whatever, on the other hand, the substance acted upon by the heat. The motive power of a waterfall depends on its height and on the quantity of the liquid; the motive power of heat depends also on the quantity of caloric used, and on what may be termed, on what in fact we will call, the height of its fall, that is to say, the difference of temperature of the bodies between which the exchange of caloric is made. In the waterfall the motive power is exactly proportional to the difference of level between the higher and lower reservoirs. In the fall of caloric the motive power undoubtedly increases with the difference of temperature between the warm and the cold bodies; .

Later theoreticians seem to have dropped the "quantity" part, so the current "Carnot limit" equation has no "quantity" variable. Only Th and Tc. Nothing corresponding to Amps or "quantity of liquid" in a waterfall. Gallons per minute or anything else sensible

This is also fairly non-ambiguous:

In a Carnot heat engine, the heat expelled to a cold reservoir can be calculated using the formula Qc = Qh - W, where Qc is the heat expelled, Qh is the heat taken in from the hot reservoir, and W is the work output

That is the efficiency formula according to the first law, or the general conservation of energy. Not the Carnot limit formula

Q is an actual quantity of heat measured in joules, so also Qc and Qh. W= work, also measured in joules.

In any event, if you have a Stirling engine running on an ice cube, my question, or Tesla's related to how much heat passes through the engine to the ice?

Heat from a fire on the hot side radiating in all directions and never entering the engine so as to be transported through to the ice on the cold side is not involved, assuming the ice is otherwise perfectly insulated on all sides, other than where it is in direct contact with the cold side of the engine.

So,..

The debate, really, has long ago been narrowed down to the heat entering the engine and specifically the heat entering and expanding the working fluid. How much of THAT heat, that went into expanding the working fluid to produce work MUST, according to the Carnot limit, pass through to the "ice" accelerating the melting rate?


Tesla suggested that because heat is energy and is converted into work by the heat engine rather than passing all the way through, a heat engine could, theoretically, run on the ambient heat of the atmosphere if maintained at a colder temperature on the opposite side, and that because the heat is transformed into "other forms of energy" after entering the engine, rather than passing all the way through to the cold, the "cold hole" could be maintained using less energy than would be gained from the conversion of the ambient heat.

In other words, you could have a kind of pseudo "perpetual motion", or a "Self-Acting engine", as it was called, by Carnot and Kelvin, who denied the possibility in their writings which Tesla had been reading.

In other words, Tesla thought he found a loophole in the 2nd Law of thermodynamics.

Arguably, we have working examples of Tesla's proposal:

https://youtu.be/caMuQbPwKYM?si=aumrc03uRkSykl3W

Evaporative cooling is driven by ambient heat. The toy bird is powered by ambient heat. You have a combined heat engine and ambient heat powered cooling system generating some electricity.

Some of the power generated is used to operate the cooling system; the bird wetting it's own head and swinging to accelerate evaporation, all within a "single heat reservoir". Arguably, something forbidden by some versions or interpretations of the second law of thermodynamics

A heat pump is really just a similar closed cycle evaporator. A fluid refrigerant evaporating in a closed cycle to produce cooling.

The suggestion however will immediately be pummeled and beaten about the head and ridiculed on the basis of the Carnot Limit. A supposed "universal law" that apparently forbids the existence of the drinking bird toy.

Personally I think that the drinking bird does exist. I used to play with one when I was maybe 4 years old, and watered it like a plant every day to keep its glass of water full

I've encountered at least one person on the science forums who said he does not believe that such a device as these drinking birds, or even a Stirling engine running on evaporative cooling could exist.

When I posted this video of a Stirling engine running on a wet piece of paper I was banned from the forum:

https://youtu.be/ARD3ctp80ac?si=0IlGAxiGZK4yXvDF

Another issue, of course, is there are various ways of measuring "efficiency". Thermal efficiency, mechanical efficiency, fuel burned vs. Power generated, "Carnot efficiency" etc

To Carnot and Kelvin's misconceptions, we can add Oliver heaviside's reformulation of James Clerk Maxwell's quaternion notation, which led aberrations in statistical mechanics as it relates to isothermal distribution theory, which contradicts the Loschmidt effect of gravity on water and air columns generating a heat gradient, well demonstrated experimentally by Graaf recently (and by the well known adiabatic lapse rate at the planetary scale). Again, accusations of 'perpetual motion machines' were thrown around...

Your LTD Stirling video demonstrating the evaporation effect is very nice, and it's ridiculous you were banned from a forum for posting it. It provides a good intro to discuss the issue you raise about defining the boundaries of a system.

The parameters of the ambient surroundings have strong effects on the performance of the engine, so they need to be included as part of the system being considered. For example, your LTD Stirling wouldn't perform well if the evaporation rate was reduced by high ambient humidity or lower ambient temperature.

Conversely, performance of the drinking bird can be greatly enhanced by reducing ambient air pressure, as this vid demonstrates:
https://www.youtube.com/watch?v=LsijnzUK3iA

Once we correctly decide what's included as part of the system under consideration, the 'over unity', and 'perpetual motion' buzz subsides.

Fool wrote: ↑Thu Apr 18, 2024 7:48 pm

Fool wrote: ↑Mon Mar 25, 2024 9:13 am
Noted equation:
Qhz-Qcz = DQh = DT• Cv•M (Noted equation)

Where:
DT = Delta T = Th-Tc
M = Mass
Cv = specific heat.

...

There is, I think, a kind of paradox in this "noted equation" that could potentially cause all kinds of problems, errors, ambiguities etc. as it is incorporated and used over and over throughout the various permutations.

Qhz is Qcz after DQh is added.

So, in other words Qcz BECOMES Qhz after the addition of DQh.

So, you have the cold working fluid at the start of the cycle with a certain quantity of energy (Qcz). To that additional heat is supplied represented by a certain quantity of energy (DQh) the MIXTURE of these two becomes Qhz.

Proposing that we subtract Qcz from Qhz then becomes ambiguous as at times, depending on the circumstances, or what point in the cycle, Qcz IS or has become Qhz. Therefore to subtract Qcz from Qhz we would have to go back in time to a point before the two became one.

If I add one drop of water to another drop of water, how many drops of water does that equal. We still have just one drop, albeit, a bit bigger than the original drop, but if we neglect to take all the variables into account this sort of thing can end up looking like 1+1=1 or 2-1=0 if for example, we propose subtracting d1 from d3 to determine the value of d2.

d=droplet
d1+d2=d3
d3-d2=d1
d1=1
d2=1
If d1+d2= 1 droplet
d3 = 1
Therefore d3-d2=0
Therefore d1=0

Various strange results if we are not extremely careful about making sure our numbers correspond with some quantifiable physical reality.

Qhz is the equivalent of 1drop + 1drop = 1 drop

Qcz and DQh are mixed to create Qhz.

Let's take for example one of the intermediate derivations. The equation:

Qcz = Qhz•(1-n)

Suppose we have an engine with 100% efficiency.

Qcz(300) = Qhz(400)x(1-1)

Qcz=Qhz(400x0)

Qcz=Qhz(0)

Qcz=0

Well,...

We added 100 joules. 100% efficiency would leave Qcz untouched by converting the supplied 100 joules(DQh) but we have just erased Qcz as well as Qhz entirely!

A rather strange result for running my little LTD engine on a cup of coffee and utilizing merely the few joules of heat transfered into the engine by some of the rising steam.

My engine and the hot coffee have vanished into a Bose-Einstein condensate as a result of the consumption of some miniscule quantity of heat supplied by some steam from a cup of coffee.

Remarkable.

More remarkable IMO is that so many scientifically trained thinking otherwise sane individuals not only think this makes perfect sense but consider it a "law of the universe".

A fraction of a Joule goes into the engine, but everything must be reduced to absolute zero to convert that fraction of a Joule into work

Of course, in a manner of speaking, 100% efficiency would mean utilizing "all the heat" in the cup of coffee "down to absolute zero".

Two different measures of "efficiency".

Are we talking about the miniscule bit of heat actually entering the working fluid?

Logically it does not require reducing the heat in the cup of coffee down to absolute zero EACH REVOLUTION of the engine just to fully utilize the fraction of a Joule actually finding its way into the engine.

Is this lunacy "established science"?

https://youtu.be/V3nNgygrmsI?si=r4K7VeLnT1otan-q

What happens if you raise an objection?

Maybe my little LTD could utilize 21% of the heat supplied.

No, that would require going to absolute zero. Perpetual motion. You can be "absolutely certain that engine is not real"

https://youtu.be/_n3Z_YBzvDQ?si=9ikyYK_JWIdw_6eH

Liar liar pants on fire. It is impossible to exceed the Carnot limit!!!!

Dirty stinking FRAUD!!!

"Perpetual motion" nut!

I fail to see how one Joule of heat more or less, converted to work, has anything to do with either absolute zero or "perpetual motion".

Stroller wrote: ↑Tue Apr 23, 2024 8:05 am
Conversely, performance of the drinking bird can be greatly enhanced by reducing ambient air pressure, as this vid demonstrates:

https://www.youtube.com/watch?v=LsijnzUK3iA

LOL...

The bird flipping over after being hit with the "duster" was hilarious.

Anyway, the whole subject is full of so many contradictions and apparent nonsense and unresolved differences of opinion I decided I needed to do some experiments of my own to try and resolve some of the issues and questions.

Like, run an engine on ice and measure the rate at which the ice melts.

I really had no idea what the outcome would be. Nobody else really had any definitive answer either.

I posted the results to the science forum asking if they would be considered "unusual" or expected.

https://www.physicsforums.com/threads/s ... ne.991714/

As can be seen, I was banned from that forum as well:
Such a rewarding area of research. Smeared, accused of faking videos, doxed by science forum members scouring the Internet for information they use to attempt to discredit me or paint me to be a "free energy", Tesla nut.

In actuality, I didn't know anything about Tesla before I started researching how Stirling engines work. I happened to come across his article about heat engines in century magazine from 1900. That is nearly the totality of my familiarity with Tesla.

Googles AI suggests the opposite of the results I obtained:

I've got a new theory, without naming names.

Some forum members here might actually be a PHPbb forum extension

https://privet-fun.translate.goog/viewt ... r_pto=wapp

Fool wrote: ↑Thu Apr 18, 2024 7:48 pm

Fool wrote: ↑Mon Mar 25, 2024 9:13 am The following is some improvements to the original post, not a direct Quote:

Fool Re- wrote: ↑Wed Mar 20, 2024 7:36 am Question: How does Qh an Qc become Q's all the way to Zero, and then, Th and Tc?

Answer:
.
...
...So Qhz should have the same relation ship to Qcz that DQh has to DQc, in other words, 'n' is the same. Basically this says that Qcz can be calculated from 'n' and Qhz,
or:
Qcz = Qhz•(1-n)

Substituting that equivalence for Qcz into the 'DQh' equation:
DQh = Qhz - Qcz (DQh equation)
Qcz = Qhz•(1-n)

Substituting and distributing:
DQh = Qhz - Qhz(1-n)
DQh = Qhz - Qhz + n•Qhz

Subtracting:
DQh = n•Qhz (#2)

Combining #1 and #2
....
.
...
Canceling 'M•Cv' top and bottom because they become one:

n=(Th-Tc)/Th <<<The final solution.
...

Your help has been much appreciated.

A few more consequences of the Carnot assumption:

I like the analysis, since if we adhere to the Carnot assumption and plug in the "correct" values, it seems to work out mathematically, but the math itself helps to reveal the fallacy of the Carnot assumption if we assume a value outside the parameters of that assumption, then the irrationality reveals itself.

DQh = Qhz - Qhz x (1-n)
100 = 400 - 400 x (1-1)
100 = 400 - 400 x 0
100 = 0 x 0
100 = 0

Or 100 = 400 depending on which operation is carried out first.


DQh = Qhz - Qhz + n x Qhz
100 = 400 - 400 + 1x400
100 = 400 - 400 + 400
100 = 400

DQh = n x Qhz
100 = 1 x 400
100 = 400

That's about all the analysis I have time for today.

Needless to say, I think fool's analysis is spot on.

The irrationality of the Carnot efficiency limit equation stripped down and fully revealed for the nonsense it really is.

All these equations are basically just variations of the Carnot limit formula. Revealed to be faulty math. An accounting error. Mathematically invalid.