Stirlingengineforum.com

I hadn't heard of a "Jake Brake" before - are they really a thing?
My driving instructor taught me how to use engine-braking, then told me never to use the technique unless necessary, as brakes are somewhat cheaper (and easier) to replace than cylinder linings!

I totally agree that the piston would have to remain "in rhythm" with the displacer, but the 'phase angle' would shift. If it shifted far enough, the engine is going to start to "skip a beat" and/or stop completely. I think you might struggle to find a servo that will run fast en...

Tom, I really don't think it is nit-picking to say that gasses NEVER contract on their own, or that the outward pressure of any gas (by definition) is greater than any inter-molecular forces, or gravitational forces, or dark energy. Besides, surely the whole point of this discussion is to try and pi...

One experiment that I have yet to get around to, is de-coupling the displacer from the power piston, and therefore having two flywheels, one driven by the piston, and driving the load; the other driven by an electric motor and driving the displacer. It seems likely to me, that this would automatical...

Tom, There is no such thing as a vacuum - the word is a useful concept, but in reality there is no such thing as a negative gas pressure. We would be in trouble if there were, as all of Earth's atmosphere would be sucked out into space. All of the demonstrations of a can/bottle/whatever imploding ar...

Tom Booth wrote: ↑Mon Aug 14, 2023 1:50 am no real work is done.

What is your definition of "Work" then?

Classically any movement of a physical object means that work was done.

In your spreadsheet diagram, do the purple sections indicate dead-space?

Tom, The simple point is that we all know that you cannot get power out of a machine without putting energy in. We can all discuss perpetual-motion as part of understanding the operation of a "perfect" Stirling engine, ie one with zero friction, but "free energy" is a whole 'noth...

Tom Booth wrote: ↑Tue Aug 08, 2023 1:58 am Apparently it's possible, once it's up and running, to shut off the air supply and recycle all of the exhaust back through the "reactor" in a closed loop.

Nope, nothing fishy about that...

Tom, It seems to me that a very simple experiment is possible, and hopefully useful, which is to de-couple the displacer from the piston of a suitable engine - probably by connecting a second flywheel. My question was meant to be somewhat rhetorical, and based round logical thought experiments but p...

Goofy, What is the point of the displacer? Is it needed?

Goofy - the problem is this: If for a moment, we ignore the "work done" on/by the piston, then what keeps the motor running? The simple answer is the alternating change in pressure of the working gas. What causes that change in pressure? The smaller reason is change of volume from the pist...

The "Cloud in a bottle" demo - it's not really an experiment - is largely a demonstration of the rather surprising properties of humidity and vapour saturation, not of temperature directly. The cloud forms because the loss of pressure moves the dew-point. (I've seen it done much more impre...

Tom,
The problem with treating ambient as being equivalent to zero, is 'pressure' doesn't agree with that at all - gas pressure at 300K is 75% of that at 400K (for the same volume) ...

What's the comment on the left, about "cold steam" all about?