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negligible too slight or small in amount to be of importance.

https://dictionary.cambridge.org/us/dic ... negligible

Twisting my words again. Negligible was not "thrown in". It's well defined. You just aren't willing to get it yet. Your effort to understand this is negotiable. Your combativeness is extraneous.

Stroller, yes. High pressure while expanding, low pressure while compressing. Heat in to get high pressure. Heat out to get low pressure.

Fool wrote: ↑Wed May 01, 2024 12:09 am negligible too slight or small in amount to be of importance.

https://dictionary.cambridge.org/us/dic ... negligible

Twisting my words again. Negligible was not "thrown in". It's well defined.

Well glad you looked it up, because it really didn't fit in with your claim that the atmosphere was "changed" enough to act as a "spring".

Context:

Pulling a vacuum on a plugged syringe requires an input of work, the gas inside expands doing work for an adiabatic temperature drop. The work input by pulling, plus the work output by the gas, are both absorbed by the atmosphere, changing it negligibly, storing the energy as a spring. The springiness is cause by the difference in pressure inside and out.

This was your counter argument to my previous statements and posted video.

Your rebuttal is clearly illogical nonsense.

It would be more honest to say you misspoke than to claim you never said what's there in black and white for everyone to see, but you continue to try and claim I'm twisting your words

Yes you spew your muddled, illogical, meaningless jumbled up trash talk in your continuing effort to discredit me and/or my research and experiments, but your lack of ability to form coherent sentences is not my doing. Your perfectly capable of twisting your own words into illogical knots without my assistance.

Feel free to clarify this sentence from your paragraph that YOU wrote, because it obviously makes no sense, or if it does, please explain.

The work input by pulling, plus the work output by the gas, are both absorbed by the atmosphere, changing it negligibly, storing the energy as a spring.

...

You just aren't willing to get it yet. Your effort to understand this is negotiable. Your combativeness is extraneous.

Another well spoken sentence.

My effort to understand is negotiable?

You really do sound like an Al that has run amuck.

Tom Booth wrote: ↑Tue Apr 30, 2024 11:56 pm I've found through experiment that work output alone is sufficient even when heat "rejection" to any "sink" has been eliminated. In fact, eliminating the "sink" almost invariably increases RPM and power output rather than reducing it, as might be expected due to heat buildup.

I'd love to see some data regarding this.

Tom Booth wrote: ↑Tue Apr 30, 2024 11:56 pm Work output is not a "flywheel driven cooling system" if that is what you are implying.

No, I agree with you that work itself takes energy out and reduces temperature. That work could be running an additional active cooling system such as a water circuit or fan though.

As I said, drowning a heat engine with buckets of cold water is counter productive.

Agree, but using small amounts of cold water in the right places might help a relatively low temperature difference system. Not so important on high temperature engines where the difference between ambient air cooling and active water cooling would only be a small proportion of the difference between hot and cold sides.

Better to incorporate some form of load balancing. Reducing heat input when work output diminishes while driving a variable load, and increasing heat input as the work output increases.

Not easy to do considering the heft and heat capacity of the hot plate. Too thin and it'll buckle under the pressure variation, losing pressure that needs to be driving the power piston.

Tom Booth wrote:You really do sound like an Al that has run amuck.

When you quote me and bold and underline everything except the word 'negligible', you under emphasize that word. That is a form of twisting others words.

I fear if rewritten even 100 times you will continue twisting it and claiming it is in error or illogical and never even raise a little finger to try to understand it. That is being combative.

You seem to be very smart. You know how these things work, both classical, and your misguided theory, please rewrite that sentence to what it should have been. In your opinion.

Questions it needs to answer.

When pulling, does the effort/energy go into the engine or out from the engine?

Where does the energy go?

Where is the energy stored?

Why does it snap back like a spring when let go?

Where does the energy to snap back come from?

What does the gas do?

Does the gas expand, contract, get hot, cold, higher pressure, lower pressure, what?

Does the gas do work and get colder?

Since energy is going into the system, why is the gas getting colder?

Energy into the engine doesn't mean hotter gas, why?

Can this concept be written concise enough so people will get it but not too long as to lose their concentration?

If the atmosphere absorbs the energy, how much does it change the atmosphere?

What cause a force imbalance?

Shall I continue? I think that is enough for now. That is a lot to put into a small paragraph. Can you do better. If so I'll use it. If not I'll stick with my first one. It is hoped that you see my dilemma now.

It is not my intention to claim the atmosphere changes, it is my intention to claim the changes to the atmosphere are negligible, and don't account for the stored energy, not in the changes. That sounds contradictory but it's actually similar. It means any changes can be ignored. Look elsewhere for why there is a spring constant. Hint, maybe force imbalance.

Fool wrote: ↑Wed May 01, 2024 6:55 am

Tom Booth wrote:You really do sound like an Al that has run amuck.

When you quote me and bold and underline everything except the word 'negligible', you under emphasize that word. That is a form of twisting others words.

No it isn't. It's giving emphasis to point out how the entire jist of the bolded text clearly states an idea or principle which with "negligible" thrown in makes the whole paragraph nonsensical on top of wrong.

I fear if rewritten even 100 times you will continue twisting it and claiming it is in error or illogical and never even raise a little finger to try to understand it. That is being combative.

My request for clarification did not leave "negligible" unbolded. It's all in context. The greater context of the conversation is still available. I'm not twisting anything. I'm trying to untangle YOUR twisted words and careless reasoning, which sorry to say is about as sharp as a bowl of cooked spaghetti noodles and just as slippery.

I would like the bolded, underlined paragraph clarified. Bolded and underlined for emphasis and identification.

Nothing is changed, altered or "twisted". That wasn't twisted and self contradictory to begin with.

You seem to be very smart. You know how these things work, both classical, and your misguided theory, please rewrite that sentence to what it should have been. In your opinion.

No thanks.

It's not my job to interpret your meaning from jumbled silly nonsense. You can't even make sense of it yourself without putting your foot in your mouth. You'd rather lie and say you never said it, blame it on the "slow student", blame it on me "twisting your words".

You wrote it, you explain it.

Questions it edit by Tom YOU needs to answer.

When pulling, does the effort/energy go into the engine or out from the engine?

Where does the energy go?

Where is the energy stored?

Why does it snap back like a spring when let go?

Where does the energy to snap back come from?

What does the gas do?

Does the gas expand, contract, get hot, cold, higher pressure, lower pressure, what?

Does the gas do work and get colder?

Since energy is going into the system, why is the gas getting colder?

Energy into the engine doesn't mean hotter gas, why?

Can this concept be written concise enough so people will get it but not too long as to lose their concentration?

If the atmosphere absorbs the energy, how much does it change the atmosphere?

What cause a force imbalance?

Shall I continue? I think that is enough for now. That is a lot to put into a small paragraph. Can you do better. If so I'll use it. If not I'll stick with my first one. It is hoped that you see my dilemma now.

It is not my intention to claim the atmosphere changes, it is my intention to claim the changes to the atmosphere are negligable, and don't account for the stored energy, not in the changes. That sounds contradictory but it's actually similar. It means any changes can be ignored. Look elsewhere for why there is a spring constant. Hint, maybe force imbalance.

My "claim" is simply; work output by the gas results in a reduction in internal energy. For a gas, temperature is the measure of internal energy. The temperature of the gas is reduced.

Further, the "pulling" by the instructor is analogous to the momentum of the piston.

In either case the gas is still doing work, expanding, losing internal energy as it helps push out the piston from the inside.

Inside pressure + instructor pulling or momentum > (is greater than) outside atmospheric pressure.

I stated all this clearly. There it is again.

You presented your spaghetti noodles as a counter argument.

I can tell you exactly what I said and what I meant.

Your words are yours. Take responsibility and stop trying to blame your lack of coherent thinking, or your contradictory presentation of your thoughts in words on me.

Stroller wrote: ↑Wed May 01, 2024 5:06 am

Tom Booth wrote: ↑Tue Apr 30, 2024 11:56 pm I've found through experiment that work output alone is sufficient even when heat "rejection" to any "sink" has been eliminated. In fact, eliminating the "sink" almost invariably increases RPM and power output rather than reducing it, as might be expected due to heat buildup.

I'd love to see some data regarding this.

First of all, what is "this"?

I've found through experiment that work output alone is sufficient even when heat "rejection" to any "sink" has been eliminated

By "sufficient", in context, I meant work output appears to be a means of reducing the internal energy (lowering the temperature, or converting heat to mechanical output) sufficient, even without external cooling of any kind.TO KEEP THE ENGINE RUNNING.

That is not to say that the engine might not run better with a greater temperature differential.

Regardless of the temperature differential, "heat" goes in. "Heat" defined as a transfer of energy facilitated by a temperature difference. The flame heating the engine is hotter than the engine so heat is transfered into the cooler engine.

Then the cold working fluid gets hot, expands and does work, converting the heat into mechanical motion. The result being that the working fluid cools back down due to work output or the conversion of heat into work. Cools back down to the original cold temperature before heat was added, OR COLDER. So that NO heat is transfered out of the engine when the now cold working fluid is transfered over to the cold side.

In other words, cooling the cold side can lower the "baseline" equilibrium or starting temperature to which heat can be added.

This additional cooling can increase the potential for expansion and work output so that MORE heat gets converted, increasing power output, but the working fluid still returns to the starting cold temperature so that there is still no heat left over to transfer out. It increases the quantity of heat that the engine can take in and convert, but that heat is also effectively converted. The colder temperature does not, as supposed increase the "flow through" to the cold "sink"

It isn't a sink, it is an equilibrium baseline "launching pad". Heat "flowing through" and out, into this "sink" is not necessary.

A lower temperature "launch pad" is necessary so heat can be added so expansion can take place, Then after expansion it is a baseline equilibrium (or zero) to return to after all the heat is converted.

It has been ASSUMED a greater temperature difference accelerates the "flow" THROUGH the engine from the "hot reservoir" through the engine and out into the "vold reservoir" but that is not the reality.

A greater ∆T increases the transfer of heat into the engine so more heat can be converted, still 100% so that zero heat is transfered to the sink.

Now a greater ∆T will also increase CONDUCTIVE heat transfer, between the hot and cold side, through BOLTS and the engine body if making these non-heat conducting is neglected. It does not increase transfer through the working fluid, it increases expansion and conversion to work output.

Tom Booth wrote: ↑Tue Apr 30, 2024 11:56 pm Work output is not a "flywheel driven cooling system" if that is what you are implying.

No, I agree with you that work itself takes energy out and reduces temperature. ...

OK, if all that is clear. Cooling the engine CAN help, but not for the reasons imagined.

Yes, initially the added cold will take away heat that lowers the temperature of the working fluid, for like maybe 1 or two revolutions. Once the cooler "baseline" is established greater expansion potential becomes actual and the greater expansion is again fully utilized for work production.

I mean, think about it. If heat is energy, how could MORE heat getting dumped into the sink faster ( more flow of energy into the cold sink) result in more heat being converted to work? That would be a clear violation of conservation of energy.

More heat flowing through AND more work output????

Data?

Mostly I do experiments and record them on video so you can see what I see.

For example, I made a simple retrofit regenerator for my LTD and extended the throw of the power piston.

Making the regenerator:

https://youtu.be/t_0mYKcy9nE

Testing and taking readings:

https://youtu.be/NtrYSpYD43w

You can see a LOT of heat around the power cylinder, power piston, even going up the power piston connecting rod.



There are three readings from the infrared camera.

Max, Min and the temperature at the cross hairs.

Min is indicated by a green square.

Max by a red square

Min and Max are FOUND by the instrument.

The red and green squares move to indicate the hottest and coldest points found by the instrument within the entire viewing screen.

Then there is the target (crosshair) temperature.

The maximum temperature is 75°F at the power piston, I assume due to friction.

The target (crosshairs) is 64°F. The crosshairs were on the top cold plate of the engine.

Min is 62°F the coldest temperature in the entire field of view. Found by the instrument to be another point on the top cold side of the engine adjacent to where I was pointing.

This is just a clip from the above video.

The temperature of "everything else" I pointed the camera at was 65°F presumably the "ambient" surroundings.

Now even allowing for some "margin of error" what are we supposed to conclude?

The "Carnot efficiency" based on the ∆T should be about 16.7%

Generally that would be interpreted to mean 16% maximum can be converted to heat and the other 84% of the heat entering the engine is "waste heat" that absolutely MUST by "LAW" be "rejected" to the "cold reservoir"

As far as I'm concerned heat from friction at the power piston should count towards "work" output. The heat must have been converted already into mechanical work to produce friction.

But the top cold side of the engine otherwise seems to average a degree or two BELOW the ambient surroundings.

This is, of course, just one of many experiments.

Experiments some believe I should just ignore, buckle down and study some "real science". This is "inconclusive". I'm "denying reality", and should try and open my mind to see the "truth" of the Carnot Limit.

Tom Booth wrote: ↑Thu May 02, 2024 1:02 am

Tom Booth wrote: ↑Tue Apr 30, 2024 11:56 pm In fact, eliminating the "sink" almost invariably increases RPM and power output rather than reducing it, as might be expected due to heat buildup.

That is not to say that the engine might not run better with a greater temperature differential.
...
A greater ∆T increases the transfer of heat into the engine so more heat can be converted, still 100% so that zero heat is transfered to the sink.

100% efficient conversion of energy from one form to another hmmm.
It looks like you think you've found the holy grail because of readings from your IR thermometer, but you need to be wary of the readings from IR thermometers, because they vary wildly when you point them at differing surfaces with varying textures, reflectivities and emissivities.

If heat is energy, how could MORE heat getting dumped into the sink faster ( more flow of energy into the cold sink) result in more heat being converted to work? That would be a clear violation of conservation of energy.

I'll get to the conservation of energy following this preamble:

In a Stirling engine, heat doesn't get converted directly to work. The intermediate step is using the heat to expand the working fluid creating a positive pressure differential between the working fluid and the ambient air pressure, resulting in force being applied to the power piston which accelerates and stores momentum in the flywheel. This 'work done' lowers the temperature of the working fluid, as does the rarification of the working fluid by the continuation of the power piston to BDC, increasing the internal volume of the engine. Absorption and dissipation of heat by the passively or actively cooled 'cold side' also reduces the working fluid temperature. In an engine in which the whole-cycle average pressure is equalised with the ambient air pressure, there will now be a negative pressure differential, which means the ambient atmosphere will force the power piston back towards TDC until pressure equalises somewhere near halfway there.

To answer your question: "how could MORE heat getting dumped into the sink faster ( more flow of energy into the cold sink) result in more heat being converted to work?"

My answer is; because having set up some active cooling (or better passive cooling), so more heat is getting dumped into the sink faster, you can also put more heat into the system faster. That will achieve a higher pressure on the cycle's expansion powerstroke, and still cool the working fluid down fast enough to get the extra push from the ambient air pressure on the return stroke; partly because more work is being done, which helps the cooling.

The point of getting more heat dissipated faster, is to overcome the bottlenecks in the system, enabling more work to be extracted without the engine weakening due to heat saturation, diminishing the differential between hot and cold sides which generates the pressure which provides the motive force.

Tom Booth wrote:Inside pressure + instructor pulling or momentum > (is greater than) outside atmospheric pressure.

I have to ask why the piston stops, if the atmosphere is so much less?

How much less is the atmosphere when at a full stroke, 200 inside, and 300 outside, when the pistons outward motion has stopped? And if left alone after the MV is gone, and the piston starts back in?

Separate questions:
Did the atmosphere change from 300? Or was any atmosphere change negligible? Is it still at 300?

Would a free piston stop if there was no atmosphere?

Where did the 1/2MV^2 energy go? Into the colder internal gas? Where did the instructors F•d energy go, into the colder internal gas?

All that needs to be answered by your, "heat-in converted to work-out", theory.

Tom Booth wrote:Then the cold working fluid gets hot, expands and does work, converting the heat into mechanical motion. The result being that the working fluid cools back down due to work output or the conversion of heat into work. Cools back down to the original cold temperature before heat was added, OR COLDER. So that NO heat is transfered out of the engine when the now cold working fluid is transfered over to the cold side.

Ending the cycle here is where error creeps into your theory. You have completely left out the resistance of the gas to being recompressed during the return stroke. That resistance requires work. That work increases the, temperature of the gas, and pressure, and resistance. It equals the same amount of energy as gained by the forward stroke, completely using up 1/2MV^2 momentum energy leaving zero to output.

In fact your theory won't end at Tc T1 V1.
It will end at T2 Th V1/V2.

You are trying to end it at T3 Tc V3 mv=0.

I hope it is realized that after heat is added, the described stroke is of the adiabatic with work, isentropic, type. Hence the return stroke is too.

Fool wrote: ↑Thu May 02, 2024 3:31 am It equals the same amount of energy as gained by the forward stroke, completely using up 1/2MV^2 momentum energy leaving zero to output.

It would if the PP and displacer were at 180 degree phasing. But they're not.

The displacer is a heat removal, and replacement device used to save the heat left over after isothermal expansion. It is not used in an isentropic expansion because the temperature after "proper" expansion would be Tc. So no extra heat to extract. Adiabatic forward, adiabatic return, Th to Tc and back to Th. No new heat at that point could be added from a Th source. No cyclic heat-in equals no cyclic work-out.

Sorry I edit my last post before seeing yours. Not trying to be sneaky. Edited this one too. Yikes!

Fool wrote: ↑Thu May 02, 2024 3:54 am No cyclic heat-in equals no cyclic work-out.

Sorry I edit my last post before seeing yours. Not trying to be sneaky. Edited this one too. Yikes!

No problem. It looks like I missed a vital part of the conversation I waded into. I'll get my coat.

I'll soon need to be spending more time in the workshop than on the forum anyway. My ebay trigger finger got twitchy. Oops.

I hope it is a very nice coat. LOL excellent purchase, and best of luck with the project.

You had a very good question. I sorta answered it with my edit so felt bad. It was an accidental edit. It was the last paragraph. I reread my post and realized it needed more. When done editing I then saw your post.

You brought up a very good point that I had to think about. Then realized I'd already answered it, kinda, sorta, and didn't want to blind sight you. So I apologize.

This is the roughest and toughest forum I've posted in. Thermodynamics gets very intertwined with itself and difficult to keep straight. Everything seems to change with one little change. Write one thing, and it means something else in another engine. Try to be generic and it will fail to apply in another engine. Talk about boiling, and it contradicts evaporation. Work-in becomes work-out. Sign convention changes in every process, it seems. Complexity becomes too simple. Simple becomes too complex. Tom seems to have difficulty with it too so I cut him and everyone lots slack. I read and reread my posts and it is still unreadable, and correct, and incorrect, all at the same time, it seems. That is why I started quoting Feynman. It takes a lot of effort to learn this stuff and only those that dig into it and broaden themselves will get it. Teachers don't teach. Students must learn in spite of the lessons of life, and errors. I started my effort with a classical four year degree, and have spent the last 20 or more years studying more and more and more.

Your question required me to teach myself more and I really appreciate it. Thank you. Please ask and comment more.

Stroller wrote: ↑Thu May 02, 2024 2:51 am
... you need to be wary of the readings from IR thermometers, ...

When you prefer to cling to 200 year old obsolete theory over modern instrument readings there can be no more progress.

When you are blind to obviously significant current video evidence preferring petrified centuries old speculations, innovation ceases.

I've spent a considerable amount of time and money on instrumentation, infrared image camera, thermocouples and the senses of my own two hands.

If all the instruments say it's cold and it also feels cold and looks cold, that seems pretty conclusive to me, the only thing left is to have results replicated and verified by independent researchers. Unfortunately, they are few and far between.

If you don't trust my video or my instruments, sense of touch or common sense, like "goofy" in here said, I encourage you to do your own experiments.

Otherwise you can carry on helping your heat run through your engine and out the other side as quickly as possible. It's good enough for NASA, should be good enough for you.

I need to construct engines that actually run and produce practical power. My NASA engine has abysmal thermodynamics. All the heat is transfered straight into the cooling system. You need a 15 foot parabolic dish and full sun, about 6000° concentrated on a point the size of a softball just to get it started for a measly 3k about 800 lbs of cold heat conducting steel and copper conducting 80% of the heat straight through to the water jacket to produce zero power.

If heat is energy, if the energy you put in goes through and out the other side it is not being converted to work output obviously

Not so obvious to Carnot 200 years ago, who believed in Caloric theory

Still a lot of throwbacks who still believe in caloric theory but don't recognize it as such, especially university academics and government financed contractors for NASA and the military.

A sad state of affairs. Keep flushing heat down the toilet to run your heat engine. Great plan!

Fool wrote: ↑Thu May 02, 2024 3:31 am

Tom Booth wrote:Then the cold working fluid gets hot, expands and does work, converting the heat into mechanical motion. The result being that the working fluid cools back down due to work output or the conversion of heat into work. Cools back down to the original cold temperature before heat was added, OR COLDER. So that NO heat is transfered out of the engine when the now cold working fluid is transfered over to the cold side.

Ending the cycle here is where error creeps into your theory. You have completely left out the resistance of the gas to being recompressed during the return stroke. That resistance requires work. That work increases the, temperature of the gas, and pressure, and resistance. It equals the same amount of energy as gained by the forward stroke, completely using up 1/2MV^2 momentum energy leaving zero to output.
...

The error is yours. Unfortunately your opinions are so firmly fixed and entrenched you're completely incapable of entertaining any thought that what you think you know with such certainty might be wrong.

I've already given my best explanation for the experimental results and other observations I've seen a dozen times.

A gas that expands does "work", and falls to low pressure and temperature hardly needs to be "compressed" at all. It virtually "contracts" on its own, with a little help from atmospheric pressure.

A rise in temperature and pressure from "compression" is negligible.

During the return stroke the gas is cold and TAKES IN heat rapidly rather than "rejecting" heat.

This heat taken in in the return stroke is then compressed by the momentum of the piston built up due to its rapid advance toward TDC.

If you don't like that explanation you can continue ignoring the clear experimental evidence for this that I've demonstrated and recorded on video over and over.

Nothing more I can do.

Stick with your calorics theory if it gives you comfort. I don't care, but I've got better things to do than argue with a stone.