Tom Booth

It's not a "physical LAW" if a physical experiment demonstrates it can be violated. 1800's style "scientific" [sic] "LAW" [sic] proclamations are no longer considered a form of valid scientific inquiry. "You" me (Tom Booth) did not propose an experiment. Swansont proposed an experiment. I for one would like to hear exactly what he had in mind, but he was shut down. I suppose next you'll be calling him Sancho Ponza I guess that's appropriate Some dragon.

You are able to adopt an idea with a "what if" attitude and think, what would we have to do to see if this is true or not. That's a great quality. There is nothing special about ice. It's just a handy way to create a temperature differential on the cheap. I've got some in the freezer here in my kitchen so I use it, but pretty obviously I think, anything cold or hot (or both) will do to create a ∆T. You can go above or below ambient (or both). I think the rate at which ice melts also makes a good gauge or measure for comparison testing. Here's an example of some previous experiments along those lines: https://www.physicsforums.com/threads/should-ice-take-longer-to-melt-when-used-to-run-a-heat-engine.991714/ There were also some posted in this forum, but that thread was locked: But if I mention it I'll get banned again I suppose. Speaking of the 2nd law. ________ I've done experiments attempting to measure or determine the "flow" of heat "through" the engine in every way I could think of. With heat applied, cold applied, ice, propane torch whatever. One thing I haven't tried is the arangement you suggested. Two engines with the cold sides back to back. Brilliant idea! The other way around might be interesting too. Sandwich the heat source between two engines. Makes measurement so much easier. The heat cannot dissipate to the surrounding ambient without going through one or the other of the engines. Very clean data should be obtainable.

You tell me. He (Swansont) just made the suggestion now, not "14 pages ago", we don't even know the details of his proposal. Unless you were joking of course.

Did you read the clip from the video transcript I posted? I've seen the video and dozens of others just like it. Feel free to post what you want, you're my hero, but I started this thread on the Stirling Engine Forum in 2010: https://stirlingengineforum.com/viewtopic.php?f=1&t=478 The basic stuff the people in here keep trying to educate me on I was studying some time prior to that. Is there something specifically you want me to get out of that video? The second law? LOL Here's another thread on the Physics forum you might find interesting, there was a "Studiot" there at the time trying to have that thread locked down as well. https://www.physicsforums.com/threads/assumed-violation-of-physics-heat-vs-work.667129/ That was 2013 You should probably be able to find me on half a dozen other similar threads on all kinds of forums debating the 2nd so-called "LAW". Evaded by whom. Such experiments I've already uploaded years ago comparing ice melting under running vs. idle engines to see what difference it might make. But I certainly have no objections to doing more/better experiments along those lines. Petitioning against scientific inquiry, great platform there. I'm sure you've got everybody's vote! What's your suggestion for an experiment. I'm starting to like you better and better Swansont! Great idea! What are the details of your suggestion?

So? The ice (or other cold object) i.e. ∆T is an independent variable, the "bounce space" is one of the dependent variables under examination, if only theoretical at this point. Time for me to take a break from this. Sorry about any unanswered responses. I will get back to them.

My experiments have not been designed to test any speculations on my part. They have been designed to test the Carnot efficiency theorem as, for example, outlined in a previous post. https://www.scienceforums.net/topic/128644-is-carnot-efficiency-valid/?do=findComment&comment=1228730 That would probably be preferable. But some form of initial cold would be necessary. There are a variety of ways of accomplishing that. Options have already been discussed.

If the ice could be completely isolated from the surrounding ambient heat so that any heat reaching the ice MUST pass through the engines working fluid That would certainly simplify measurements. That is the point of Ghideon's excellent suggestion (or "rhetorical question"). Heat flow via the heat engine to the ice if present could be more easily determined. Of course 100% elimination of all avenues of heat transfer other than the working fluid inside the engine is probably unrealizable. There must of course be an engine body of some sort which might conduct some small amount of heat etc. But such unwanted transfers could much more easily be reduced to an absolute minimum with the engines sharing the "sink" between themselves, literally between the engines. The heat would then have to be transfered through one engine or the other in order to reach the ice. This eliminated the issue about the potential conductivity of the insulation. There wouldn't:t be any. I would be willing to say that at a minimum, with the two engine arrangement Ghideon proposed, the ice should melt eventually, but MUCH much much more slowly. If there is heat transfer, than 2 engines both transferring heat to the ice simultaneously would double the heat input and the ice should melt much more rapidly, relative with some control. For the ice to NEVER melt would mean there must be some heat transfer in the opposite direction out of the ice rather than into it. I do not rule out that possibility, as, as I've said before, I've seen some evidence that the Stirling engine behaves similarly to a Vuilleumier machine, pulling heat from both the hotter and the less hot ("cold") heat exchangers, (or top and bottom plates).

I surmise it to be the basic unconscious assumption behind concepts such as heat "flow", "reservoir", etc. Use of such phraseology conjures up images of a fluid flow.

How it that not a variable? I explained briefly what I mean already, but to elaborate: There is a ceiling and a floor. Obviously if you make something colder and it contracts, lowering the floor, creating more distance between the floor (maximum contraction) and ceiling (maximum expansion) you have provided more room for expansion, which is the actual source of power output (conversion of heat into work). I could elaborate further if you still don't get it but that might involve posting some video.

As far as any potential employment, I have no idea what your talking about. How do you feel you were misrepresented? Hmmm... Work output counts for nothing? If my Stirling engine drives a generator that lights up a village, powers machinery etc. We should recon that "irreversible" work output as waste heat? Well that solves the problem I guess. Every work output will resolve back into heat eventually. Lightbulbs, toasters, radiant heaters, cloths dryers, microwave ovens etc. all produce heat. So we can subtract all that from the efficiency. That should balance things out nicely.

A theory is just a theory. To establish it as a reality requires testing in reality, not another "exercise in theory".

Did you read my later full response? There is no debate about the increase in efficiency but rather what the actual cause might be. The cold applied is the primary cause, but I'm suggesting that there might be a secondary cause that explains the increased efficiency without resorting to the heat "flow through to the sink" (or cold reservoir) concept. The cold might just provide more "bounce space" for expansion work. I mean, if I might make an appeal to logic, and common sense, if heat is the fuel for a heat engine how does dumping additional "fuel" to a now colder sink improve performance? In a Stirling or other "pure" heat engine the heat is a consumable; an actual fuel for the engine. One that "disappears" with no residual "waste" product.

That’s the only variable that changed. And work increased from zero to some nonzero value, so there is no arguing about the increase in efficiency It's not "the only" variable that changed. Room for expansion work has increased also as a result. It may be that this increased contraction/expansion space accounts for better engine performance (performance of more expansion work) rather than a more rapid or voluminous "flow" of a magical caloric/heat to the non-existent "cold reservoir". The problem in running tests has been the probable inadequacy of insulation and the insulation acting as a heat conductor rather than an impediment. That's why I'm rather excited about Ghideons suggestion. It has the potential for virtually, if not entirely eliminating a wild variable.

That's fine, but this is not the lounge room for idle chatter or endless off topic banter, or a treatise on the Studiot theory of thermodynamics, or the Tom Booth theory for that matter. As far as I'm concerned the thread can wander where it will, but just please stop whining if I fail to respond to posts irrelevant to the topic I'm interested in focusing on. Relevance? Is that my "thought for the day" or what's your point exactly?

If you do not want to read or respond to posts in an intelligent and constructive way, or make some contribution towards the objectives proposed, why not go waste your time elsewhere and bother someone else with your inanities. You pretty obviously know absolutely nothing about how a real Stirling engine operates, but if you are going to mislead people I do feel it is within my place here to point out the errors and inaccuracies in your statements as compared with reality. What you posted about the Stirling engine cycle bears no resemblance to either Robert Stirling's original invention or any subsequent models or modifications. Compression of the working fluid results in heat not cold. It's elementary thermodynamics. Good question. While I agree Kinetic theory provides the best explanation and I generally advocate that, I'm not at all certain of it's absolute accuracy. For example I picture gas particles under high pressure in an engine cylinder something like marbles packed together in a jar. Can some be actually zipping around at near light speed while others float about aimlessly? I think "partial pressure" may afford some explanation. Larger air molecules may be packed tightly together while smaller molecules move in between. Maybe possible for a Hot Air engine with mixed gas but what about an engine charged with pure helium and hermetically sealed? More pressure on a compressed gas and there is phase change to liquid with something like an 800X reduction in volume depending on the gas, the transition is not as sudden as generally supposed perhaps, there is a gradual contraction of the gas. "4) What exactly is expanding and contracting in a single particle ?" Perhaps nothing. Presumably there would be no intermolecular forces between particles if there is only one. Not just "becoming sceptical" he systematically demolishes the theory: The list of facts cited by Carnot is too long to reproduce here.

LOL... You equate physical LAW with traffic rules and regulations? You really are in sorry shape. In need of a dose of reality, lost in idealizations and abstractions. If the book says, it must be true. Yes you do need to run the traffic light if someone is alleging it's actually IMPOSSIBLE! if you are going to test the claim.

I should point out a typo in the quote from Carnot's unpublished writings: "best" should have been heat: Can't say how that cropped in, possibly a. OCR error in whatever online copy I c/p'd. (Some PDF) As far as your diagrams, I've seen these so-called proofs a thousand times (slight exaggeration, but dozens certainly). As I recently mentioned to Ghideon this thread is not entitled elementary thermodynamics. You seem to have all your ducks in a row ready to post an entire treatise on the subject from start to finish, that is neither appropriate nor necessary. If you want to play the headmaster of your own thermodynamics course I would suggest you start your own thread on the subject. The focus here is very narrow: Is the so-called Carnot efficiency formula valid or applicable to a Stirling engine, and is it falsifiable: can it be tested experimentally. If you feel your chart in some way relates to that topic feel free to carry on, if not, carry on anyway if you like, but don't expect a response from me for your off topic derails that threaten to swell to encyclopedic proportions. It's "proper" context is there for all to see. Maybe you could elaborate on whatever it is you might be trying to say there. How would you interpret Carnot's statement in whatever it is you consider "it's proper context" ?

Your point? A clip from the transcript: Stirling engines are precision engineered machines. Even most of the toys or models. Many people who attempt to build one fail to get it to work, we have them coming into the SR forum all the time asking for help because their engine will not run and they can't figure out why. There is nothing spontaneous about these machines. Few people even understand how they are supposed to work. NOBODY really understands fully how they ACTUALLY work I'd venture to guess. They certainly do not work in the way traditionally supposed. BTW, I appreciate the concern, but generally speaking people can stop trying to teach me about fundamental thermodynamics. Sorry for pointing out where you were wrong/ignorant. If you can't take the heat get out of the kitchen as they say. This thread is about how a Real Stirling engine works and if the dreamt up arbitrary Carnot limit actually applies or not. Your description of how a Stirling engine operates "opposite" to other heat engines or the Carnot cycle is simply wrong, regardless of what you might have gleaned from Googling up a Wikipedia article that is also wrong. You might try taking your own advice: Where is your experimental proof of this? There are at least two interpretations of the Carnot limit, one is basically valid IMO, the other is apparently (based on experimental results and other observations) hogwash. Which interpretation do you think the little engine might be violating? 1) That at best, discounting friction, inertia etc. Provided 1000 joules of heat the engine can only utilize the 1000 joules SUPPLIED and no more. Or 2) That at best the engine can utilize 20% or less of the 1000 joules SUPPLIED to it. At best, only 200 joules are available to be converted. I've seen both interpretations espoused, sometimes in the same article, the writer apparently unaware of the contradiction.

@Tom Booth here is an example where the scientists probe at the limits of applicability: From my general reading on the subject, it is claimed that this Carnot limit applies to ALL heat engines, broadly defined. My use of the equation seems to be in harmony with how it is generally applied in courses and lectures on the subject, example problems etc. Here is a typical example chosen at random out of a search result just now. https://blog.mide.com/thermodynamic-theory-of-the-ideal-stirling-engine For the authors qualifications, here is his LinkedIn profile page: https://www.linkedin.com/in/luke-saindon-43971066 Note the following claim: I happen to be doing this exact experiment, testing this claim or assumption. Somehow I cannot equate "cooling the cold section" with my doing the opposite: insulating the cold section with a combination of acrylic, Aerogel and a glass globe. And yet the engine did "run continuously", once it got going. There is not any misapplication of the Carnot limit on my part. I'm just testing it's general application as given, as others are applying it. My experiments have consistently produced results contrary to these expectations, (if no [external] cooling is applied to the engine's cold side it should not be able to run). I'm postulating that in lieu of external cooling, perhaps the engine is effecting internal cooling as a result of expansion work. This does not seem to be too much of a stretch of the imagination, IMO from general thermodynamic principles. The only real barrier to acceptance of that postulate is the (in my estimation arbitrary) Carnot efficiency limit "Law" or theory or assumption.

Something curious happened during the experiment that seemed rather unusual, I don't know what to attribute it to or what if any significance it might have. Normally these engines are intended to run on a cup of hot Coffee and are rather difficult to get started and to keep going requiring a relatively high ∆T compared to other Low temperature difference engines. The most notable feature is perhaps the loud irregular clatter from the displacer. This particular model has a magnetic displacer. That is a small magnet attached to the piston lifts the displacer as the piston reaches the down, full compression position. With expansion the piston pulls away, the magnetic pull on the displacer is broken and the displacer drops down. This is a very noisy operation as the displacer click up against the top of the chamber then drops back and hits the bottom There is usually no end to this clatter of the displacer as long as the engine is running, but in the experiment, after the engine was kept running for a very long time on the continuously available steam heat, the engine fell almost completely silent. All I can imagine is that the engine achieved some homeostasis where the displacer was virtually suspended, caught by the magnet each revolution, before hitting the bottom, then dropped before hitting the top, just oscillating in between. Covered with insulation I can only guess. Perhaps running for so long the heat softened the plastic so it made much less noise. I can't really be sure without running it that way again without insulation or with a window or scope inside. It's probably insignificant, but I'm curious to find out what was actually going on for the engine to run so smooth and silently when normally it is so annoyingly loud. Another thing that struck me as unusual was that while trying to fix the insulation my finger inadvertantly got caught by the flywheel and it actually hurt a little and the engine did not stop. These engines usually stop at the touch of a feather. It seemed to have more torque than when running under normal circumstances without insulation. This has been a consistent observation. These engines run with either more speed or more torque or both and also run longer (if the heat source is finite, like a cup of hot water) when the cold side is insulated. By "these engines" I mean LTD Stirling engines generally, not just the magnetic type.

Valid criticisms to some extent as it was a completely unplanned raw video taken in my kitchen when I happened to have some time. I recorded what I thought relevant at the time. If I recorded everything the video would have been 3 hours long. Ten seconds is no time to cool down after sitting over steam for ten minutes. Another problem was the flywheel on the #2 engine was buried in the insulation which I made as thick as possible. I had tried trimming it away with an exacto knife, but had not done a very good job, so there was some drag on the flywheel of the second engine from the flywheel contacting the insulation. I kept trying to push the insulation down out of the way but it kept puffing back up. If you watch more of the video it can be seen clearly that at one point the engine wouldn't run, then it almost stops and I push the insulation down and it picks up speed and keeps running. I think it's pretty clear the problem was the insulation causing drag on the flywheel. After that first video, the next day I cut away the insulation a little more and with a slightly better set up, made a second video but only posted it too the Stirling engine forum because of the issues with posting video here. In the second run I was able to work out some of the problems like steam getting through and under the blanket and inside the glass globe as well as the insulation rubbing. And some better temperature readings in preparation for using the probes, which I have yet to do.

The only reason for having the first engine in the video at all was so people could see the type of engine that is under the insulation. So I didn't bother recording the start up for the first engine which is largely irrelevant IMO, but the first engine went through several false starts as well. That is very typical for this type of engine. I just got the first engine going off camera and then restarted the film when I had it warmed up and ready to run.

If you watch carefully there is a beep and jump in the video of sorts between the time water is poured into the steamer and when it boils. That actually took a few minutes for the water to get up to a simmer. The first engine had all that time to warm up and was ready to run when I restarted the camera.

My phone has a limited recording capacity, so I had paused the video several times. With the first engine without insulation the engine sat on the steamer until the water got up to boil so the engine was already well pre-heated over the simmering water for some time. I paused the camera during the warmup period. The second engine with the Aerogel blanket insulation had a cold start. It is quite typical of Stirling engines to take some time to reach operating temperature and have a few false starts if not yet warm enough. ------------ The reason Stirling engines in general typically need a few pushes to get going is that they have some characteristics of a "Maxwell's demon" and it usually takes some time for the hot and cold working fluids to become segregated. How this takes place is that during compression the working fluid is displaced to the hot side of the chamber. Then with expansion the working fluid is displaced over to the cold side. I'm sure you are aware that when a gas is compressed it heats up, expanded it cools down. So while turning the engine over by hand, at one part of the cycle, the gas is compressed and moved to the hot side, then for the other half of the cycle the gas is expanded and moved to the cold side, back and forth., back and forth rapidly until a temperature differential is well established and the engine can run freely. Of course this segregation or heat pump activity is maintained once the engine is running well.

It has been the observed outcome of my several experiments. Heat applied to the engine on the hot side does not appear in a measurable form in the quantities suggested by the Carnot efficiency formula at the presumed "sink" (cold side). So, this has lead me to ask the question: if heat is not passing through to the ice, what could be the reason? My measuring instruments don't seem to be broken. So is the Carnot efficiency equation really valid? The first response I inevitably get is that I'm a crank or whatever, but hay, I've recorded it all on video. There is nothing preventing anyone from doing these simple, inexpensive experiments. I've had engines running on the flame from a propane torch on the hot side with hardly any change whatsoever at the "sink". If the heat isn't passing through, this leads me to doubt the Carnot efficiency equation, or the interpretation that states such a large percentage of the supplied heat in actual Joules absolutely MUST be "rejected" to the "cold reservoir". So, can this be tested? Maybe there is some basis for concluding that the equation does not actually apply to Stirling hot air engines. I mean Carnot et al were talking mainly about steam engines. In a steam engine some water is brought to a boil in an enclosed vessel where it builds up pressure. A small amount of steam, under high pressure is admitted to the cylinder with the piston at or near TDC through a valve which is then quickly shut. The pressurized steam is then allowed to expand performing work pushing the cylinder. The steam is then allowed out to a condenser. Well, we have the latent heat of evaporation stored up in the steam at boil, then released as heat of condensation. It is natural and actually accurate to conclude that the steam has in some way "transported" heat from the boiler to the condenser, because it has. A Stirling Hot Air engine however does not involve any such phase change. There is only the expansion and contraction of a gas. Should we expect that the same amount of heat be "transported" in a hot air engine as in a steam engine?