Carnot reveal for Tom

[Tom Booth]

Matt,

I find it interesting that people that are attempting to break the laws of physics, to make a perpetual motion machine, or any other fracture of any of those laws, either don't realize they are attempting to break a law, nor attempting perpetual motion. They seem to think it will have little effect on physics. They also, typically, pronounce their ability to do so long before producing any working machine. The difficulties are usually written off by stating that they are difficulties and can be solved. They then seem to want help from others to overcome those difficulties.They also leave out important theoretical information as to how this is accomplished.

You have not provided any PV or TS diagram for your Voodoo cycle. Tom has not provided any for his hot potato engine. ...

I don't believe I ever made any "overunity" claims regarding the "hot potato" engine. The idea behind that was simply increased heat transfer into the engine by "bumping" the regenerator at TDC.

I've told you repeatedly on prior occasions that I'm not so much trying to invent any new engine but rather, just observing and trying to understand how existing examples of Stirling engines actually work In that regard I have posted a couple actual (not theoretical or "idealized") PV diagrams based on real time readings and measurements.

These actual readings show a definite drop in pressure below atmospheric pressure

Generally speaking in a Stirling engine, by the time it reaches "operating temperature" the working fluid has already been heated and expanded and much of it has leaked out past the piston. What's left is rarified; less dense than atmospheric air.

I think, as a consequence of this, when the relatively few remaining hot molecules deliver a push to the piston these molecules are cooled (loose kinetic energy to the piston) and are then attracted to each other resulting in a rather strong vacuum. The PV readings show a definite drop in pressure below atmospheric pressure which stays below atmosphere nearly all the way from around BDC almost back to TDC, maybe 5/6ths, the last 1/6th or so of the return "compression" trip the pressure finally climbs back to above atmospheric, only exceeding it at the last instant

https://youtu.be/dvomod6SsA0

And another:

Resize_20230522_110819_9316.jpg (272.58 KiB) Viewed 9580 times

[VincentG]

Forget for a minute the phase change of the water. All the gas in the glass tube cares about is that heat has left the upper bulb and it can now condense to form liquid, and transfer its heat to the tube, which has transferred its heat to the water, which has transferred its heat to a phase change, which has only occurred because the atmosphere has a lack of humidity that allows evaporation...and so on and so forth.

There would be no such thing as cold, if there were no heat(energy) to flow into it. Otherwise it would just "be". Similar to how there would be no up or down without gravity or a planet to orient yourself. Or there would be no darkness without light.

[Tom Booth]

As far as temperature, I've posted actual recorded experiments earlier in the thread that show no appreciable "heat rejection" at the cold side of the engine. Just a few among some dozens of similar experiments:

viewtopic.php?f=1&t=5547#p19572

But in previous conversations, you dismissed this so accusing me of writing anything off seems misplaced.

[Tom Booth]

Forget for a minute the phase change of the water. All the gas in the glass tube cares about is that heat has left the upper bulb and it can now condense to form liquid, and transfer its heat to the tube, which has transferred its heat to the water, which has transferred its heat to a phase change, which has only occurred because the atmosphere has a lack of humidity that allows evaporation...and so on and so forth.

There would be no such thing as cold, if there were no heat(energy) to flow into it. Otherwise it would just "be". Similar to how there would be no up or down without gravity or a planet to orient yourself. Or there would be no darkness without light.

I don't think that there is any real proof that the evaporated methylene chloride actually transfers heat anywhere. The gas cooling and condensing could be the result of adiabatic expansion, the same as cloud formation which by definition does not involve heat transfer.

True, the process of evaporation results in cooling to a temperature that allows the substance to expand and cool and condense but that an actual transfer of heat takes place is, I think, an assumption.

Suppose we don't wet the birds head but instead insulate that and apply a little heat to the base. Will the bird fail to operate due to a lack of "heat rejection" at the head?

Will heat rejection take place anyway, in spite of efforts to insulate the head because the insulation will act as a conductor?

This video is interesting, but doesn't really address these specific questions:

https://youtu.be/c-0-zH4Ip7w

[VincentG]

I am only referring to the drinking bird example. I have never discounted the heat pump effect of a running stirling engine, only that I have not observed the same results.

[VincentG]

Will heat rejection take place anyway, in spite of efforts to insulate the head because the insulation will act as a conductor?

Yes. And if you can change this please let me know so I can lower my home heating bill to nearly zero.

Edit: my point is only that everything transfers heat, despite our best efforts.

[Tom Booth]

Will heat rejection take place anyway, in spite of efforts to insulate the head because the insulation will act as a conductor?

Yes. And if you can change this please let me know so I can lower my home heating bill to nearly zero.

Edit: my point is only that everything transfers heat, despite our best efforts.

Well, for all I know the methylene chloride is cooling below ambient temperature due to adiabatic expansion making heat transfer to ambient impossible, if we assume that heat only "flows" from a warmer to a cooler zone. I would not make any assumptions before actually carying out some actual experiments.

[VincentG]

That would be plausible but it is in a gaseous state at room temperature, so no internal cooling should take place.

[Tom Booth]

Assuming you are right, for arguments sake, and heat transfers from the fluid to the glass to the wet felt from there heat is utilized in the state change from liquid to vapor. We can draw the system boundary at different locations and come up with different answers but my point is, heat as a form of energy can be transformed into some other state or other form of energy resulting in a drop in temperature.

The process of evaporation, in a manner of speaking causes sensible heat to vanish. Heat is not carried off or "rejected".

Personally I don't think you can eliminate the evaporation process as part of the drinking bird "system", if actually using evaporation to cause the bird to operate.

For a very long time I assumed without question, more I'd say I "knew" or thought I knew, that a Stirling engine ran by being heated and then having the heat removed, or a process that included "heat rejection". And I might add, could never run without a flywheel. At this point those assumptions seems questionable, if not entirely wrong, conclusively, so I'm hesitant to make any assumptions regarding how this other heat engine (the bird) operates.

[Tom Booth]

...
200 years, and counting, of trying to prove Carnot wrong, and still no working models. Thousands have tried and are still trying. Thousands, and counting, have failed. Yes, I'm one of them. I now can see why they fail. Good hunting.
...

Well, this may be true or it may not be.

Taking a look at the previously posted liquid air machine I can see a few places where energy has not been fully utilized:

Polish_20230706_051729381.jpg (249.88 KiB) Viewed 9537 times

Compressing air generates a tremendous amount of heat. If a refrigerant is boiled to cool the compressed air, why could that not be used in a closed loop to power a turbine?

The liquid air produced could drive an engine.

Probably some additional Stirling engines could be operated from the heat generated and/or cold somewhere in this system, especially if it is true that a Stirling engine actually transmits little or no heat through to the sink. For example, a Stirling engine running on ambient heat could have its "sink" on the liquid air tank.

Historically Charles Tripler who produced liquid air on an industrial scale casually stated in an interview that he found that he could use the liquid air to drive his compressor (driven by an ordinary steam engine) and produce ten more gallons of liquid air using just three gallons of liquid air to drive the steam engine.

Tripler was roundly ridiculed in the press by scientists who characterized him as a fraud. As a consequence of this disbelief and negative publicity he was ruined.

Personally I do not believe he was a fraud. He was shipping wine barrels of liquid air all over the country.

John Gorrie made similar statements in regard to his ice machine invention.

He too was criticized as a fraud and driven into bankruptcy. He disclosed in his patent that his machine could operate very economically, driven almost entirely by the heat extracted in the course of the ice making process.

I don't believe these individuals were frauds. They had working productive machines.

Resize_20230706_054502_2394.jpg (157.33 KiB) Viewed 9537 times

There were quite a few others. Scott Robertson is currently working on his website where he lists the many inventors:

https://www.aircaraccess.com/achf-intro.html

Apparently in the process of compressing air, ALL of the energy used to compress the air goes to waste as heat. 100% of the energy used to compress air is lost as "waste heat". Similarly when you compress a spring, all the energy used to compress the spring is lost as heat, and yet, the spring springs back! When the spring is released it gets cold, eventually it reabsorbs that lost heat. It is a rather strange phenomenon that all the energy used to compress a spring is lost as heat yet the spring springs back returning all that energy before it can fully recover the heat.

The same thing appears to be true of air. When compressed, all the energy used for compression is lost as heat. When decompressed or allowed to expand, the air gets cold. It acts just like a spring. Think about that for a while.

There are air car inventors who claim to have driven their compressed air vehicles across country without refueling by using some clever way of recompressing the cold exhaust from their air motor.

Cold air contracts naturally, by itself. Think about that for a while.

Why will some scientists take it upon themselves to go after these inventors like rabid dogs? Apparently they sincerely believe that they are defending the general public from charlatans, cheats, liars and fraudsters.

You say, mr Nobody, that you are one of those who tried and failed, and you know why they failed.

Why don't you share your experience then?

[VincentG]

The process of evaporation, in a manner of speaking causes sensible heat to vanish. Heat is not carried off or "rejected".

Maybe the concern is with the word "rejected". I do not view it as a loss in a negative sense. I'm not sure how heat can vanish. It is a form of molecular energy that can be converted or stored. As I've said before, without cold there is no heat. So the transfer of heat to a cold space, whether by external cooling or expansion resulted by the work of a piston, is the only reason these engines work in the first place. The relatively cold environment we live in is a free source of energy potential. There would be much less energy potential if we inhabited Mercury, for example.

[Tom Booth]

The process of evaporation, in a manner of speaking causes sensible heat to vanish. Heat is not carried off or "rejected".

Maybe the concern is with the word "rejected". I do not view it as a loss in a negative sense. I'm not sure how heat can vanish. It is a form of molecular energy that can be converted or stored. As I've said before, without cold there is no heat. So the transfer of heat to a cold space, whether by external cooling or expansion resulted by the work of a piston, is the only reason these engines work in the first place. The relatively cold environment we live in is a free source of energy potential. There would be much less energy potential if we inhabited Mercury, for example.

You say it yourself: heat " is a form of molecular energy that can be converted...".

If you convert something it no longer exists in its original form. If heat as a form of energy is converted from the internal molecular motion of a hot gas into the motion of a revolving crankshaft and flywheel leaving the gas cold in the process, the original heat energy that was transfered to the engine no longer exists in the form of heat that can be transfered back out of the engine.

To transfer it out, the motion of the engine would have to be stopped or slowed down by friction or conversion to another form, like electricity to power a space heater. The heat in the gas, as HEAT has effectively vanished, in its place you have a revolving flywheel.

OK, so you can say the "heat" has been stored in the flywheel but that is not really accurate. The flywheel could be stone cold, it did not receive any heat (in the form of "thermal energy") No heat was transfered to it, yet the heat did "vanish" from the hot gas leaving it colder.

On a microscopic level it is all kinetic energy I suppose, but perhaps that model is outdated.

Regardless, another more accurate way of thinking about it is to say that the air molecules in the working gas inside the engine collided with the piston transferring kinetic energy so the fast moving air molecules slowed down and the piston moved an almost imperceptible distance.

It takes trillions and trillions of impacts from tiny air molecules to move the comparatively enormous piston a hairs breadth, with every impact the gas grows colder (the fast moving hot air molecules move more slowly having transfered their kinetic energy to the piston)

[Tom Booth]

...So the transfer of heat to a cold space, whether by external cooling or expansion resulted by the work of a piston, ...

Well,.. no.

The heated expanding gas does the work on the piston.

I've posted this video, probably a dozen times already but it explains it well

https://youtu.be/PMKPZuCj9a0

The only thing I disagree with is if tha particle hits the piston when the piston is stationary it will come away with the same energy. If the piston moves it won't, and the piston in an engine is designed to be able to move as easily as possible by an expanding gas, but it takes more than one impact from a single molecule.

[Tom Booth]

Anyway, in a running Stirling engine the piston is always moving except briefly at TDC and BDC.(we give the flywheel a boost to get it started)

To be effective many molecules need to be heated rapidly and simultaneously, but the result, when the molecules hit the piston is the same, they transfers itheir energy to the piston and grow cold. The molecules of expanding gas striking the surface of the piston are what keep it moving.

Unless of course the piston is moving in towards TDC, then the impact transfers kinetic energy the other way and the gas temperature increases.

The only way a Stirling engine could run without a flywheel or connection to a crankshaft (free piston) is for enough molecules to transfer kinetic energy to the piston, getting cold enough, that the gas "contracts" drawing the piston back in, reversing it's course.. merely cooling the gas to equal the outside ambient would only slow it down or stop it, but not draw it back in.

There is also a matter of relative temperature between the piston and working gas. It the piston is cold it will absorb actual heat from the gas, so the engine needs to be brought up to "operating temperature".

[Tom Booth]

Another takeaway from that video, if the gas molecules strikes a wall that doesn't move, it bounces off retaining its energy, assuming the wall is also the same temperature.

Therefore, it would seem, theoretically they could bounce around inside the engine pretty much indefinitely without energy loss. Until they happen to strike the moveable piston, during a power stroke, assuming that the inside of the engine is relatively warm throughout.