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I recently found an old dirt devil vacuum powered brush head attachment. It has a squirrel cage style fan blade and a belt drive to a brush head. It has a surprising amount of torque. Just for fun I hooked it to the vacuum and ran it up for a few minutes loaded and unloaded while checking temperatur...

Conversion to work is not "direct thermal transfer", and it is also not "reversible", and for the most part, cannot be "recycled". I am not suggesting perpetual motion. I am suggesting an improbable theoretical cycle where assuming no losses, by temperature degradation...

The way I would phrase this, assuming the heat is not in fact destroyed, by any other means than direct thermal transfer, is that the same heat energy, if it could be recycled at 100% efficiency, would produce its equal amount of work over and over again.

Well Tom you said it yourself. If the answer to my question violates the laws of thermodynamics, then it is certainly outside of tradition.

I would prefer all parties engage in the discussion.

Stroller and Fool represent the more traditional, proven, mainstream science. Tom is certainly on the fringe, along with me perhaps, just looking for answers.

Regarding the latest round of discussions, any extra weight presented to the piston when the starting condition is only 14.7psi will no longer allow a doubling of volume. The more weight, the more the expansion becomes closer to Cv. This, at the sweet spot, should minimize the amount of energy neede...

Stroller wrote: ↑Tue May 21, 2024 5:24 am It's the action of the expanding gas "consuming" energy that I am interested in. Is internal energy really reduced when the gas expands, other than by conduction losses to the surrounding colder surfaces of the engine. And if so, how exactly? The ...

Well, "adiabatic" IS without any kind of thermal transfer in or out of the gas. To me that is a less complex scenario than isothermal which for every joule of work done by the gas an equivalent amount of heat is added to replace it. Very true, but my point being that an adiabatic expansio...

Tom that was a good response and about sums up what I would ask. By "free expansion", I believe Stroller and I had settled on the baseline of the gas expanding against one atmosphere. So it's still doing "work". I think, for now, thinking in terms of an isothermal expansion is le...

In any example, we would use the minimum amount of gas needed to do the work at hand. By degrades, I mean into a lower temperature state. It's the action of the expanding gas "consuming" energy that I am interested in. Is internal energy really reduced when the gas expands, other than by c...

Heat isn't a substance, it's manifested as a flow of energy from a hotter body to a colder body. Energy is neither created nor destroyed, but it can get translated from one thing to another. In our example, the extra Joule started out as additional energy passed from the external energy source into...

Regarding the copper verses steel block, I assume it is a weight difference. Just remember moving the displacer up and down is a temperature difference. Although both would move, I would think there would be a difference. I don't know how much. Pressure would be constant for both, but higher for th...

Moving to the 5lb weight makes a tremendous systemic difference when the starting pressure rises 4psi from 4 extra pounds across one square inch of piston surface.

I'll think about your response until tonight.

I thought I had filmed the heavy steel block but I did not. It moved just the same as the copper bar.

https://youtube.com/shorts/WPtcVRK35nU? ... 3tzGUxqpzn

I'm an engineer, not a forensic nitpicker. I do practical calcs good enough to get the job done, and don't bother about negligible additional forces. That's because nothing ever lives up to its theoretical promise anyway. If you want to know how many millimetres or extra pascals the gas compressed ...