Ghideon

That's why I keep my mind open to new ideas* and use heuristics to navigate around old failed stuff. I know for instance that a Perpetuum Mobile of Villard de Honnecourt does not work; it does not matter if it is painted in a new color. Regarding the idea in the opening post; do we neglect the mass of some of the moving components? *) In my profession new ideas emerge almost daily. Not new physics but new ideas that really challenges what is established.

Bold by me. Awareness about the limits of physics may save time; focusing efforts on what is possible and rejecting the impossible ideas early.

Are we discussing what is possible according to established laws of physics or new/modified laws of physics?

Ok. How about conservation of energy?

There seems to be four stirling engines in the first picture, what are those for?

It's just a quick idea based on what you posted earlier, nothing worth exploring further if there is no interest.

What you proposed: But you have not given any details as far as I can see.

Side note while I wait answers to some previous questions: Have you thought of combining the two types of arrangements? It is probably too mechanically complicated to be useful or realisable but may trigger further ideas: Arrange an even number of Stirling engines in a "Stirling Ring"; hot against hot and cold against cold in a circle. In this thought experiment, what could be the result when applying your ideas?

You seem to cherry pick the first picture? What about the picture that show the experiment at a later state?

Good idea. PoE (Power over Ethernet) may also be applicable; one PoE & LAN signal repeater somewhere between house and caravan Personally I prefer a wall jack and a patch cable between wall & equipment.

I disagree, there are too many unknown variables. I don't see how that experiment helps you debunk established theories. I'll take a look at this later!

And without ice as a complicating factor?

One reason for me to ask questions and try to get into the details about your hypotheses and your possible explanations is to find possible improvements in the experiments. For instance if ice was crucial to the experiment I would suggest various ways to get repetitive results from that. If low temperature is the thing that actually is required I intuitively try to simplify how to cool the things instead of how to manage the ice. And maybe if the problem is to get the engines staring when cold side is at ambient temperature that can be managed as well. It all serves to remove variable things that others could have problems to repeat or that may be tricky to reproduce in your setup. None of these requires an explanation of the result before running the experiment but it helps to create a setup that have fewer sources of errors while at the same time does not introduce bias regarding the hypothesis. Why do you have to ask; isn't it obvious since you know thermodynamics? (And I will not try to explain; you asked me not to:)

Thanks for your reply. My intention was to support your comment by adding a scientific example where Carnot terminology was used in what I believed was at the edge of its applicability. Sorry if I misinterpreted and added confusion. I have not (yet) possess the knowledge to comment on the results or methods in the paper. Thanks; that seems to be the point I tried to make by providing the example.

Based on personal experience from my garage; the second law of thermodynamics can be compared to the contents of a spilled assortment box. The contents of the box tend to end up in a disorganized mess. The probability of the contents of the box becoming sorted is low. (Side note: Here is a video describing the statistical aspect of thermodynamics; the description does not rely upon archaic steam engines: https://www.khanacademy.org/test-prep/mcat/chemical-processes/thermodynamics-mcat/v/second-law-of-thermodynamics)

@Tom Booth here is an example where the scientists probe at the limits of applicability: ... Source: https://www.nature.com/articles/nphys3518.pdf (I do not wish to take the discussion off topic, we discuss the case of Carnot limit for macroscopic engines. Just wanted to share in case there is any interest in papers discussing limits of applicability in the context of Studiots comment.)

I''m thinking as an experimenter. When ice is added, for instance under insulation between two engines, I find it complicated to see when all the ice actually melts; I may disturb the experiment. Instead I prefer to use only a thermometer. Thinking again, this is a good idea: What if you instead of ice have a thermometer probe pre-cooled and inserted at the cold side? Then you can see the temperature all the time and the pre-cooled probe takes the role of the ice? If something more massive than the probe is required you can attach the probe to some object of suitable size and shape (The probe may heat too quick when moved from freezer to engine setup). Maybe a thin sheet of metal?

According to established science or your ideas?

The ice just complicates the scenario; would it be possible to discuss an ice-less scenario? I can't follow your descriptions, sorry. Can we agree that you expect a cooling effect on the cold side? I mean, if ice does melt slow in your experiment then, according to your description, the running engine is keeping the temperature lower that ambient at the cold side? If so we can discuss the consequences and a simplified experiment without the errors and failures that the ice will cause.

@Tom Booth did you see my post regarding an addition to the experiment? https://www.scienceforums.net/topic/128644-is-carnot-efficiency-valid/?do=findComment&comment=1228275 (May have been overlooked since there were some x-posting and editing)

Let's outline the logical next step by using one addition. Assume the setup works; We have the Stirling engine running and cold plate insulated with an adjacent Stirling engine or good enough insulation. Place the running engine(s) in a well-insulated box. All the work performed by the engine(s) will be friction loss in the engine or movement of air inside the box. These losses will heat the air inside the insulated box. Conservation of energy means no energy enters or exits the box and no energy is permanently lost in the box, just changing between heat and mechanical work. The running engine(s) keep the cold side cool, and the losses are heating the air. In principle the box is a sealed system, and the engine will never stop since a permanent difference in temperature is established. This goes against my understaning of physics, but it seems to follow logically from your ideas and your conclusion of experiments? Can you provide a reference? It could add value to the discussion. (As far as I know it is ok per forum rules to link to further reading)

The logical consequence of your idea seems to be that you are just one simple component short of creating a major breakthrouh in physics. But I do not believe in such machinery therefore my question was rethorical. But I would be happy to be proven wrong.

Sharing is ok with me but note that my question was a rethorical. Elaborating may take the thread off topic but I’ll clarify if you wish.

Thanks for your comments! I guess proportions are also a concern; a really large piece of ice on a low power engine allows for other factors to have significant impact? Also freezers are maybe not built to precision, hysteresis may allow for the ice to have different temperatures. A few degrees may make a difference when a small engine melts the ice.

That seems reasonable. But under the insulation the temperature will be rather stable once the Stirling engine has run for a while? Temperature will likely vary depending on the load and added heat (and more) but if the effect you propose is there the temperature should read below ambient if the insulation is good enough. Initially it is good enough tho show experimentally, beyond doubt and in a repeatable fashion, that effect you predict exits; exact numbers can be found in later experiments?