A little over a month ago I posted this drawing on the Stirling engine forum
There is some explanation about the operation there:
Forum. but the thread was a different topic and the drawing was not actually intended as a viable "invention" or working engine per se, but the intent was to illustrate a basic principle about Stirling engines and how they ACTUALLY operate, (IMO), which was, that although the engine
can operate as a result of
the existence of a temperature difference, it does not operate as a result of a "flow" of "heat" between hot and cold, like water flows down from high to low.
The hot and cold portions of the engine remain separated. So I "invented" this hypothetical device based on a fire piston and the compression and resultant heating of air and the expansion and resulting cooling of the same air.
If instead of compressing a "fire syringe" or fire piston, the syringe is
pulled out, expanding the air instead of compressing it, the result is cooling.
So, this device was intended to capture the temperature difference generated by alternately compressing and expanding the air in a Fire Piston type closed cylinder.
The difference from a fire piston is the bottom slides back and forth so as to capture the resulting "heat of compression", then the heated bottom can slide over during expansion when the air is cold (Cold not only due to being expanded, but also cold due to the heat having been "taken out", as it was absorbed into the "regenerator" or heat absorbing medium in the bottom of the cylinder.)
The "regenerator" (heat capturing base) moving into the cylinder at the point when all the air is fully compressed into the small space in the bottom of the cylinder while the piston is all the way down.
Then as the piston moves up and the gas(air) cools the regenerator sneaks off to the side to "protect" and conserve the heat so that it does not get lost back into the cold expanding air in the cylinder.
A similar "regenerator" might also capture and preserve the cold.
In other words, this engine is acting as a heat pump. But, with the addition of a flywheel, it could also run as an engine, it is, infact, intended as a representation of how a Stirling engine ACTUALLY operates. Not by allowing a flow of heat between hot and cold portions of the engine, but rather by maintaining a separation between hot and cold, as well as, in fact, creating and maintaining that separation, like a heat pump.
The piston "bounces" on a "spring" of hot gas. Bouncing with more force each cycle as the temperature of the gas increases.
Anyway, with a slight modification of this concept engine:
We, in theory, could have a fuelless diesel type engine/generator.
All it does basically is compress air to create a temperature difference and use a thermopile to convert that temperature gradient into electricity.
There is not necessarily any need for exchanging air if the cylinder were made of a good heat exchange material, such as aluminum, the expanded cold air in the cylinder would simply absorb into itself the surrounding ambient heat through the cylinder walls which heat could then be concentrated with the subsequent compression. This heat in turn captured and utilized both to keep the engine going as well as generating electricity via the thermopile in the base.
Then, of course, this could evolve further into a more powerful multi-cylinder engine.
There is additional explanatory text in the previous post on the Stirling Engine Forum here:
https://stirlingengineforum.com/viewtopi...774#p24774 mostly after the text: "Imagine two regenerators..." A few paragraphs down.
A warning however about the Stirling engine forum. The owner apparently has passed away so for the past few months the forum has been almost entirely overrun with spam and who knows what. All the spam has mostly been confined to new threads.
