Stirlingengineforum.com

.

Tom Booth wrote:Matt has proved...

So you now trust his math and logic as if it's proof? I suppose it could be considered a mathematical proof. You know, he and I agree on the mathematics here often.

I'm not sure what you are implying. If it's that, a hot power piston behaves differently than a cold power piston, I agree. Matt has definitely put up quite good logic suggesting that. I would caution definitive comments on it until some actual tests have been performed with indicator, and dynamometer, diagrams have been measured.

It is why I keep recommending the inverted LTD Stirling Engine test. Both inverted and upright. One way will have a heated power piston. The other way will have a cold power piston. Dynamometer measurements will show which outputs more power. Plus it's easier to heat the bottom and either cool or insulated the flat plate side.

I'm just not sure it's significance is matched for when displacer volume is a lot larger than power piston volume. The
LTD Engines have a similar stroke and a lot larger diameter on the displacer.

.

Fool wrote: ↑Fri Nov 15, 2024 7:50 am .

Tom Booth wrote:Matt has proved...

So you now trust his math and logic as if it's proof? I suppose it could be considered a mathematical proof. You know, he and I agree on the mathematics here often.

I'm not sure what you are implying. If it's that, a hot power piston behaves differently than a cold power piston, I agree. Matt has definitely put up quite good logic suggesting that. I would caution definitive comments on it until some actual tests have been performed with indicator, and dynamometer, diagrams have been measured.

It is why I keep recommending the inverted LTD Stirling Engine test. Both inverted and upright. One way will have a heated power piston. The other way will have a cold power piston. Dynamometer measurements will show which outputs more power. Plus it's easier to heat the bottom and either cool or insulated the flat plate side.

I'm just not sure it's significance is matched for when displacer volume is a lot larger than power piston volume. The
LTD Engines have a similar stroke and a lot larger diameter on the displacer.

This was not Tom's quote, it was mine.

The end goal of a power piston driven off the hot end is to have it be larger than the displacer, or at least the same size, within a 300k-600k cycle. I have little doubt that my new engine will run with a power piston of 50cc or greater and a displacer of 150cc, within a 275k-373k cycle, so the enormous ratios of an LTD are irrelevant IMO.

Fool wrote: ↑Fri Nov 15, 2024 7:31 am .

Jack wrote:Well I guess the electron cloud could be seen as a beach ball.

Nice try, but no. Electron clouds 'touching' never happens. They get close but bounce before touching. The electron clouds increase in size very little with heat, compared with the mean free path observed for a gas, that increases a lot during, expansion with cooling. Think about just the forces of the electron clouds being the shell of a ping pong or pool ball. They don't come into play until bouncing. The closer they get the stronger, but the electron clouds don't quite touch. Mean free path is why a gas is many times less dense than a solid or liquid. Temperature increases speed. Increased volume increases mean free path, lower density.

Solids and liquids have bonds between the electron clouds. Solid bonds are stronger than liquid bonds. Those bonds are described using the Lenard-Jones Potential Theory. Gasses by the kinetic theory, and fluid dynamics continuity equations.

I agree with you that there is no cohesive logic to the beach ball analogy. How does it account for phase changes, solid, liquid, gas? It doesn't.

You (fool) just love to go on and on talking "knowingly" as if you actually had some idea what you're talking about, when quite obviously you don't.

Maybe you were a teacher. A lot of times teachers in school think they have to have an answer for everything and will prattle on and on. The class full of 2 year olds is an easy sell and they know it doesn't really matter what they say. Same goes for some college level teachers. The students really don't know the subject so the teacher can get in the habit of just making stuff up like it's an embarrassment not to have an answer to every question even when you don't.

You sure like to play teacher in here, acting like we are all your students when the majority of the time you just haven't got a clue what your talking about, detailing "facts" off the top of your head with no concept of reality.

As the atoms approach one another, their electron clouds gradually begin to overlap.

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

There are hundreds of references all saying the same thing. Electron clouds overlap. Molecules attract more than they repell up to the point where the electron clouds overlap.

You should really do a little actual research before spewing your verbal diarrhea all over the forum.

Jack wrote: ↑Thu Nov 14, 2024 10:01 pm Well I guess the electron cloud could be seen as a beach ball.

I still don't see what you, Tom, think heat itself is then, in your theory.
How does the beach ball get larger? What does heat do to it to make it larger?

Pauli exclusion principle.

Not that that actually explains anything, but what I get out of it is that basically there can only be so many electrons in a particular molecules' orbital "shell".

When there are too many electrons orbiting the nucleus some electrons will have to "expand" outward into a higher orbit. In the process, the gas molecules repel each other to make room for the higher orbit.

https://youtu.be/INYZy6_HaQE

When heated, electrons also "jump" to a higher orbit. So if several gas molecules are at a stable distance apart and energy is added in the form of heat, then the electrons jump to a higher orbit, but then the orbits overlap and some electrons have to jump to an even higher orbit.

Basically the molecules need more room as the electrons jump to higher and higher orbits so that the orbits do not overlap too much.

Bottom line is, IMO if the molecules were not already at a stable distance, but were flying past each other not interacting much at all, they would just be like fish swimming in the ocean or birds flying. So what if some swim or fly faster than others?

For heat to expand a gas, logically IMO anyway, the molecules must already have their electron clouds adjacent or partially overlapping, otherwise they would not be close enough to need to "expand" when heat is added and the electron orbits jump to higher levels.

I'm using my own frame of reference here and I hope you can explain your theory in that same reference.

I'm working around a "de Laval" nozzle.
Basically flow is chocked and reaches mach 1 only for then to be expanded and reaching higher speeds.
How would your theory explain that sudden rise in speed and sudden drop in temperature of the fluid?

.

VincentG wrote:This was not Tom's quote, it was mine.

The end goal of a power piston driven off the hot end is to have it be larger than the displacer, or at least the same size, within a 300k-600k cycle. I have little doubt that my new engine will run with a power piston of 50cc or greater and a displacer of 150cc, within a 275k-373k cycle, so the enormous ratios of an LTD are irrelevant IMO.

Opps. Sorry. Sounds like a worthy pursuit. Good testing.

.

.

Jack, the de Laval nozzle starts out high pressure and temperature. It converts that thermal energy into velocity at a lower Temperature and pressure. It appears to have density drop as well.

You probably already have seen the following:

https://en.m.wikipedia.org/wiki/De_Laval_nozzle


Tom is completely unaware at how small, atoms, electron clouds, and molecules are. He can't fathom how much smaller that is when compared to the density of gas. He even contradicts himself. The enlargement of the electron cloud after absorbing photons, is miniscule compared with the mean free path in gas molecules. Let alone after expanding through a nozzle.

The Pauli exclusion principal forbids two electrons from being in the same orbit. The electron orbits of two molecules can not overlap.

Tom, think about the mechanics of bringing two molecules or atoms together. If it has full orbitals, like helium, it has perfect symmetry, not polar. As two helium atoms get closer their electron clouds get pushed and pulled offset from their protons. This gives them a slight +/- charge distribution and a slight attraction. It is called Van der Waals force. As they get closer the electron shells get closer. That then turns into electron electron repulsion as the orbits of each try, but don't quite overlap. As the electron clouds push each other away, repulsion force, the positive nucleases push too, extra repulsion. The electron clouds, and protons won't touch.

There are more quantum effects for ionic, covalent, and metallic bonding, but they are negligible in gasses. Gasses have no bonding. That is why modern/classical theory uses the kinematic model for gasses.

.

Jack wrote: ↑Sat Nov 16, 2024 1:59 am I'm using my own frame of reference here and I hope you can explain your theory in that same reference.

I'm working around a "de Laval" nozzle.
Basically flow is chocked and reaches mach 1 only for then to be expanded and reaching higher speeds.
How would your theory explain that sudden rise in speed and sudden drop in temperature of the fluid?

To begin with it's not "my" theory.

Van der Walls forces of molecular attraction, Lennard Jones potential and Pauli exclusion principle.

I think it is universally recognized these are more accurate and much more realistic models of gas behavior, and the behavior of molecules generally, than the classic "kinetic theory of gases" and "ideal gas law". I'm just giving my own take on these principles. They adequately explain what I'm seeing in my experiments where the older classical models do not.

The rise in speed I think is simply, Bernoulli's principle, the venturi effect. Nozzles are not really related to how gas behaves in a sealed off chamber.

I haven't really thought about it in that context.

Fool wrote: ↑Sat Nov 16, 2024 3:29 am .

Jack, the de Laval nozzle starts out high pressure and temperature. It converts that thermal energy into velocity at a lower Temperature and pressure. It appears to have density drop as well.

You probably already have seen the following:

https://en.m.wikipedia.org/wiki/De_Laval_nozzle


Tom is completely unaware at how small, atoms, electron clouds, and molecules are. He can't fathom how much smaller that is when compared to the density of gas. He even contradicts himself. The enlargement of the electron cloud after absorbing photons, is miniscule compared with the mean free path in gas molecules. Let alone after expanding through a nozzle.

The Pauli exclusion principal forbids two electrons from being in the same orbit. The electron orbits of two molecules can not overlap.

Tom, think about the mechanics of bringing two molecules or atoms together. If it has full orbitals, like helium, it has perfect symmetry, not polar. As two helium atoms get closer their electron clouds get pushed and pulled offset from their protons. This gives them a slight +/- charge distribution and a slight attraction. It is called Van der Waals force. As they get closer the electron shells get closer. That then turns into electron electron repulsion as the orbits of each try, but don't quite overlap. As the electron clouds push each other away, repulsion force, the positive nucleases push too, extra repulsion. The electron clouds, and protons won't touch.

There are more quantum effects for ionic, covalent, and metallic bonding, but they are negligible in gasses. Gasses have no bonding. That is why modern/classical theory uses the kinematic model for gasses.

.

Anyone who has spent a few hours researching these topics will see how clueless and ignorant you are, so I won't bother pointing out your several false statements, which have already been addressed a few posts back.

viewtopic.php?p=27029#p27029

You will just keep on and on with your 1820's view of gas behavior, while pretending you are an expert in all other fields of science you're completely clueless about.

Fool wrote: ↑Sat Nov 16, 2024 2:08 am .

VincentG wrote:This was not Tom's quote, it was mine.

The end goal of a power piston driven off the hot end is to have it be larger than the displacer, or at least the same size, within a 300k-600k cycle. I have little doubt that my new engine will run with a power piston of 50cc or greater and a displacer of 150cc, within a 275k-373k cycle, so the enormous ratios of an LTD are irrelevant IMO.

Opps. Sorry. Sounds like a worthy pursuit. Good testing.

.

LOL...

Like facts, theories or ideas are wrong deserving of your criticism or "a worthy pursuit" to be praised depending on who posted it.

.

Tommy wrote:To begin with it's not "my" theory.
.....

I'm just giving my own take on these principles. They adequately explain what I'm seeing in my experiments where the older classical models do not.

Yes. I'm glad you recognize it isn't a theory, because there is nothing scientific about your "own take". It is a completely fraudulent illogic collection of incompatible buzzwords. You are going against almost all science out of there. You mix big words incompatibly from the wrong areas of science, while ignoring the information that plainly shows your error. You fail to use the modern classical theories correctly, so of course they don't work for you. I use them and they explain all those observations you report. You often refuse to measure needed data and set up your experiments to fail. You are in good company with Martin Fleischmann and Stanley Pons. They failed to do science correctly too. Now they are useful as a bad example. You just lack any degree to make your mistakes more persuasive. Otherwise you would have a legion of idiot followers too, until your inevitable failures.

Your take won't even explain the blatantly obvious easily verified fact that gasses always push. One little fact in your face that won't go away by denying it, any more than denying the Earth is round will make round Earth theory go away. You are a worthless cherry picking science denying quack.

When shown your errors, you start cursing. Good luck with that.

Tommy wrote:Like facts, theories or ideas are wrong deserving of your criticism or "a worthy pursuit" to be praised depending on who posted it.

You are getting worse. It's getting harder and harder to find anything worthy of praise from your rambling confusing scrambling of buzzwords, name calling and cursing. But, I liked some of your work with the drinking birds. Besides VincentG added some pursuits to his agreement with Matt. I just thought it was you contradicting yourself, as you often do. Sorry I got confused as to who said what. My point there was Matt needed experimental verification, and expansion of his analysis, before finishing. And yes VincentG already.avrees with Matt on many things. You are the outsider here.

When you three or more get on your free energy, same as beat Carnot kick, I'm apparently the outsider here, although Matt agrees with the Carnot Rule for most engines. He's just brainstorming hopeful thoughts. I just look for correct analysis, nothing more. Be correct, we all make enough mistakes without bashing science. Your bashing is just being mean and denial.

Example of how Tom reacts the others: Jack asked how your theory explains a de Laval Nozzle. You just lashed back that it wasn't your theory. You then threw out a few buzzwords that have no use in explaining a de Laval Nozzle. Buzzwords that deal with solids and liquids, without explanation of how gasses behave. LOL

Get some formal education, so you can learn what science is, before you start bashing it. You are so mixed up, that it is pathetic. You need to seek out a professor and have several one on one question sessions too.

Fool wrote: ↑Sat Nov 16, 2024 10:34 am .

Buzzwords that deal with solids and liquids, without explanation of how gasses behave

You consider Van der Walls, Lennard Jones potential and Pauli exclusion principal "buzzwords"?

Those are just topics interrelated to "real" gas behavior.

I didn't "lashed back" at Jack. Those are not "my" theories.

I don't know if they relate to fluid dynamics or de Laval Nozzles, particularly. As I said, I haven't thought about it in that context.

Unlike you I don't pretend to know everything.

Fool wrote: ↑Fri Nov 15, 2024 7:50 am Matt has definitely put up quite good logic suggesting that. I would caution definitive comments on it until some actual tests have been performed with indicator, and dynamometer, diagrams have been measured.

When it comes to hot vs cold PP, this graphic is a home run since it's nothing more then how the ideal gas law plays out upon similar comparison. Note equal PVT values for all 3 engines in frames 2 and 3. So, if you buy into current thermo then you're left wondering exactly what happens between frames 3 and 4 to arrive at frame 4 values for hot PP Essex vs cold PP Stirling.

Granted, these are all ideal sequences with esoteric piston dwell, but nevertheless inline ideal gas law. The only test that these values require is a few quick checks that I didn't screw up somewhere, otherwise these values are rock solid (from a theoretical view).

If you buy into the ideal gas law and stare at this graphic for awhile it should become clear that typical cold PP Stirling is a dumb idea from both output and efficiency viewpoints. In distant past, I was often accused of sleight of hand. No, not cherry picking, but more like fudging numbers whereby I could shoehorn 'claim' to fit impossible scenario. However, what I was really doing was merely finding a simple (tho rare) example that cuts thru any BS, like how a 3-4-5 triangle proves the Pythagorean Theorem.

Fool should have no issue with these values, but I understand their implication (1) cold PP sucks (2) but by how much ??? A close look at frame 4 for Stirling vs Essex will reveal that quantifying this difference is more academic than practical, since it's readily apparent that cold PP requires more input for less output vs hot PP. My deep dive into "another gamma anomaly" was an attempt to quantify this difference via a crude finite analysis which is currently in limbo. Nevertheless, I was able to conclude to my satisfaction that typical cold PP Stirling suffers from massive work loss when DP gas passes thru regen to PP. My major question is not exactly how much is this work loss, but how the academics could miss this.

Matt, I think your depiction of the Stirling cycle is not accurate. At least not by traditional design standards.

You don't appear to include, or account for, in any way, the standard 90° advance which IMO changes the dynamics considerably.

Also, you don't appear to make adjustments for the temperature and pressure drop that results, or "theoretically" should result from work output during expansion (power stroke).

These two things combined tend to minimize or eliminate the transfer of heat through the regenerator.

Another consequence of your modeling not taking the previous into account is compression and expansion and the resulting elevations and reductions in temperature and pressure are not apparent. Introducing heat 1/2 way into the power stroke, I think, tends to concentrate additional heat on the heat input side.

The effect of the later is to "pump" heat away from or out of the cold chamber into the hot chamber further curtailing heat migration from the hot to the cold side through the regenerator or otherwise.

So overall, for these reasons as well as actual observations and readings of running engines, I'm not so sure about "massive work loss when DP gas passes thru regen to PP" though admittedly, not too long ago I was thinking along the same lines.

Thermal readings, if they can be believed, seem to show a sharp divide between hot and cold at what seems to be a rather stable demarcation point
It might be noted that the 62°F reading at the top cold plate would be, again, if it can be believed, about 2° below the general ambient room temperature.

.

And the hot side is boiling water at 87F?

Sounds very inaccurate.

.