Carnot reveal for Tom

[Tom Booth]

If you lift a weight 800 miles and lower it back down the best 100% that you can hope for is zero zero work total in and or out. Your cycle energy acquired is zero. Work in rasing the weight, minus work out descending the weight will equal zero.

The exact same thing can be said about an adiabatic spring. Push it in and get it he same energy back out. Zero heat involve with either. Adiabatic pairs cancel each other and zero work or heat is obtained or used.

Both processes obey the laws of thermodynamics however neither is a process of heat. Heat works differently because it has to be converted to pressure and volume changes. Those pressure and volume changes are dependent on temperature. .(...)a temperature difference is needed, so there will be a pressure difference.

Assuming a Stirling engine to be a kind of oscillating "air spring", that is, adiabatic expansion and contraction, your analysis above and/or elsewhere seems to neglect the fact that as a gas expands and does work, temperature of the gas drops.

As I see it you get an adiabatic "bounce" at TDC which converts heat into velocity. Velocity is converted into work lowering the temperature so atmospheric pressure can take over and effect a reverse process.

As atmosphere drives the piston in, it too does work and the temperature of the atmospheric air drops in the cylinder above the piston and contracts, making the next adiabatic bounce at TDC considerably easier I imagine, so more energy can go out as work and less needed for pushing atmosphere out of the way.

What people are calling a "metronome" Stirling or metronome engine is interesting in that regard.

The metronome engine uses an extended tube, like a fluidine engine (but without liquid) I think maybe that makes it more difficult for atmosphere to move in and out of the cylinder augmenting this atmospheric."contraction" above the piston.

Imagine the atmospheric air above the piston acting like a hammer delivering blows to the piston at BDC doing work on the piston to smack it inward then withdrawing, like a hammer bouncing off a nail.

The heat input to the engine is working the other end in the same way.

[Tom Booth]

If heat in a gas is simply the kinetic energy of the air molecules themselves individually, then an overall "pressure" is just a localized phenomenon and just as there are high and low pressure systems in the atmosphere due to uneven heating there can be localized high and low (oscillating) pressure zones around, above and below the piston .

[Tom Booth]

There is something else I've been meaning to experiment with.

While doing this type of experiment, covering the engine with a glass cylinder to keep out drafts:

https://youtu.be/l2XcnN6QdfA

After running covered, for .maybe 45 minutes, when I would take the sheet of ceramic fiber insulation off to see inside and take temperature readings the engine would abruptly stop running.

I thought this was rather strange, but it seemed reproducible, however it required letting the engine run long enough for the air (possibly some steam rising up also) above the engine to get warm. (Though the top surface of the engine was still near ambient)

On the theory that atmosphere is responsible for driving the piston back inward, I imagined the warm air trapped above the engine was imparting kinetic energy to the piston and lifting the lid, letting out this warm air, and letting in a sudden cold draft was enough to interrupt the action.

This is admittedly wild speculation but I would have thought letting in a cold draft would cool the top of the engine, if anything and cause the engine to run better

But we aren't really talking about the top cold plate of the engine. That was blanketed by aerogel and a draft should not have had any immediate effect. What was exposed to the trapped air was just the small top of the power piston, just about 1 cm in diameter.

What I thought might be worth trying is something like a very small heating element above the power cylinder.

This may have implications for the flame licker.

I've been puzzled by the way those engines operate for some time.

Is it possible that hot air drawn into the confined space of the cylinder helps drive out the piston without what would normally be considered "pressure". As the valve is open so how could pressure build up? The piston is moving away from the valve during intake, and yet, the air being drawn in is very hot so should be carrying considerable "kinetic energy"

Anyway I have some small heating elements taken out of electronic type cigaret lighters. I thought I might try heating the air immediately above the piston on a little LTD engine and see if it has any noticeable effect, like the flame at the cylinder opening of a flame licker, increasing the "kinetic energy" of the atmospheric air being drawn into the cylinder during the "compression" stroke.

I know, in theory, that is not how a flame licker is supposed to work, being considered a "vacuum engine", deriving it's power from cooling/contraction, but some observations suggest otherwise.

[Tom Booth]

Take this big flamelicker

https://youtu.be/Vof1GCSGPh0


Maybe not the most well made engine and maybe not timed as well as it could be, but watching it run on extra slow motion I have difficulty understanding how it could run at all based on vacuum.

It has a ballbearing resting on a port on the top of the cylinder as a pressure relief valve that opens during the return stroke. Just after the crank rounds BDC and the piston starts on the return trip this ballbearing pops up, and it looks pretty heavy so some pressure would need to build before it would actually lift but this happens, what seems to me to be very early on the return stroke.

On "expansion" or intake of the flame/hot air the intake valve does close just a little before BDC which could account for some vacuum, but the relief valve appears to me to open about the same distance after BDC. So the potential for generating much vacuum seems negligible and as far as conferring any driving force to the piston, virtually non existent.

So what might be an alternative explanation for what is driving the piston?

I thought perhaps what is going on is this:

Resize_20230712_225436_6365.jpg (155.02 KiB) Viewed 25950 times

The hot air and flame is being drawn in through a rather narrow orifice creating a jet of hot air that impacts the piston creating a localized high pressure zone, even though, at the same time low pressure in the cylinder continues to draw in the hot gas creating the jet that propels the piston.

If true, that seems rather incredible, but I don't see how the engine could be driven by a vacuum while the relief valve is open...

Unless, maybe there is a similar localized high pressure that develops on the return stroke lifting the relief valve even while a vacuum is drawing in the piston at the other end of the cylinder.

Some kind of "pressure wave"???

Logically the piston could not be driven by the same stream of air it's movement is drawing in, but perhaps the air being drawn in is accelerated by the simultaneous heating. Kind of like a jet engine in reverse.

[Tom Booth]

Some food for thought.

Imagine the outside atmosphere is the "combustion chamber" Which, in actuality it is. Combustion takes place outside the flame licker. A pretty big "chamber" but it is pressurized to 15 psi.

The small orifice is the throat of the nozzle or venturi type restriction to initially accelerate the expanding gas/fuel burning mixture.

The inside of the engine is the expanding nozzle which oddly enough, according to this video, causes the expanding gas to accelerate even more as it expands beyond supersonic speed.

As a "short" the video cannot be embedded here AFAIK.

https://youtube.com/shorts/c7AHkuUqlFI?feature=share

Not particularly trying to sell the idea, just trying to solve a puzzle. My observations don't correspond with the usual explanation. So how to explain the odd behavior in the engine I'm observing?

Without understanding how the engine actually works, there isn't much chance of making any real improvements.

It may all just be guesswork at this point, but suggests possibilities for experiment.

[Tom Booth]

This might be easier to implement.

Instead of a vacuum fill the chamber with some gas with very low heat conductivity.

CO2 is fairly cheap and easily obtainable and has a conductivity about 1/2 that of atmospheric air.

Polish_20230713_140732097.jpg (440.97 KiB) Viewed 25926 times

[attachment=0]

[Tom Booth]

Tom,
...
You seem to think it is possible to get the same efficiency out of a 273K cup, 8oz, of water heated to 373K, as a, much larger volume of 273K heated to 274K with the same input energy.

Well, in theory, why not?

(...)

You must think everyone is stupid, ignorant, and unmotivated. People are, and have been, trying to break the laws of thermodynamics and Carnot since before Carnot. They have been trying everything you talk about here. If you want to take away the cooling side of engines, go ahead. My guess is you will grow old, or will learn why it is impossible, as I have. I have not stopped trying. ...

Well, I'm happy to hear that.

I don't make judgements about other people's views and opinions. I recognize that whatever I think or believe, it could be shown or proven to be wrong by a demonstration or experiment.

All I can do is weigh the evidence and give my honest opinion based on my own viewpoint and experiences.

If I have a blind spot, I would be more than grateful if someone took the time to enlighten me, but I have yet to hear any really convincing argument that would persuade me to accept the Carnot LIMITATION on faith, without any concrete experimental evidence to back it up.

It's quite possible "everyone" else is smarter than I am and I'm sure everyone IS actually smarter in some way.

I'm quite open as far as listening to and considering all the available evidence, views and opinions.

I do think some well thought out experiment could shed light on the topic one way or the other.

I, to say the least cannot agree with this final post on the physics forum after they locked the thread and banned me from there:

Different machines and setups can produce different results. But those results will always be consistent with the laws of thermodynamics, so one should never conclude that what they are seeing contradicts the laws of thermodynamics, but instead should interpret the results from within that existing framework.

Reference: https://www.physicsforums.com/threads/s ... 714/page-3

So I'm supposed to deny the evidence of my own eyes. Ignore the outcome of my own experiments?

What kind of science is that?

[Fool]

A fool lives in his own little world believing what his own little eyes and actions provide, ignoring other viewpoints until cognitive dissonance provides his only peace. He then fabricates his own belief. Denial becomes his only friend.

Science is about elimination of factors that lead to mistakes. Good science requires good equipment and good help from good experienced scientists.

Be wary of what you are denying, your own belief in what you seek with your own means and beliefs, or ages and volumes of scientific logic by people smarter, and less so, that have studied widely and seen differently.

The biggest fool of them all isn't the one whom listens and ignores, it is the one whom eliminates any valid help and blathers on endlessly with himself. Despite the power to agree or disagree with one's own foolishness.

[VincentG]

Or so says the fool to the "fool".

[Tom Booth]

A fool lives in his own little world believing what his own little eyes and actions provide, ignoring other viewpoints until cognitive dissonance provides his only peace. He then fabricates his own belief. Denial becomes his only friend.

Science is about elimination of factors that lead to mistakes. Good science requires good equipment and good help from good experienced scientists.

Be wary of what you are denying, your own belief in what you seek with your own means and beliefs, or ages and volumes of scientific logic by people smarter, and less so, that have studied widely and seen differently.

The biggest fool of them all isn't the one whom listens and ignores, it is the one whom eliminates any valid help and blathers on endlessly with himself. Despite the power to agree or disagree with one's own foolishness.

Well said, in particular:

"Science is about elimination of factors that lead to mistakes. Good science requires good equipment and good help from good experienced scientists."

If we read Carnot's writings both his published book and his later unpublished journals, we find that he did, with the help of many other scientists, finally realize his mistakes, bringing his thinking in line with Tesla, that heat is a form of energy or "movement" that can be converted to other forms and that therefore cold should not be necessary in order to derive "motive power" from heat, and that heat could be converted into work in its entirety.

His unpublished journals however were,... well,... unpublished, in the possession of his family, I believe, so thermodynamics developed without the benefit of these later insights and corrections.

[Tom Booth]

Maybe we could return to the subject of conducting some experiment before Mr. "fool" interjected his opinion that making real world experimental observations is "foolishness".

What is foolish IMO is blindly following a 200 year old convention that has never been empirically verified.

Especially when such experiments are relatively simple and inexpensive. No excuse not to really.

[Tom Booth]

Tom,
...
You must think everyone is stupid, ignorant, and unmotivated. People are, and have been, trying to break the laws of thermodynamics and Carnot since before Carnot. They have been trying everything you talk about here. If you want to take away the cooling side of engines, go ahead. My guess is you will grow old, or will learn why it is impossible,...

https://youtube.com/playlist?list=PLpx2 ... heZwZqToa2

Seems pretty darn possible to me.

Styrofoam, acrylic, aerogel, those are not fans and radiators or water cooling jackets.

[Tom Booth]

BTW, though most people here probably already know this.

The first time I did this experiment I was expecting to end up demonstrating just that; how it is impossible to run a Stirling engine without a cold side, without letting heat out to keep the cold side cool.

When I started filming, I honestly thought I would come here to the forum and show how the engine would quickly slow down and stop from overheating. I had no real reason to expect otherwise.

It was only after the engine kept running, sometime later, out of curiosity I thought I would use a stop watch and count the revolutions, that should at least show the engine was slowing down due to the heat bottleneck.

But after watching the video several times, checking and double checking, the engine was actually running faster after the final bit of insulation was added.

I did this experiment over and iver in every possible way using every kind of insulation I could think of.

So what exactly is "impossible" about doing away with the cold side of a Stirling engine?

There's nothing to it.

I'd like to see anyone actually get the dang thing to slow down and stop like it's supposed to. Let me see someone actually prove the Carnot theory RIGHT!