I briefly floated this idea in the "high temperature displacer" thread, but as I think I may actually try building such a thing soon, thought a thread to document the experiment as things progress might be in order.
The idea brings a lot of things together.
First of all, I would never have considered such a thing if not for previous experimental findings in the Stirling engine thermodynamics thread and the Tesla heat engine thread. Why?
Well, a Stirling engine, built like a crucible, from refractory, heated up from the INSIDE, inside a microwave oven, doesn't have any "sink". No real "cold reservoir" for any heat to escape to. Electromagnetic radiation, microwaves, may pass through the engine, but can't escape the microwave oven. Aren't supposed to anyway.
The idea also arose as a result of investigations into how to make a high temperature displacer... which lead to making a foamed glass displacer in a microwave kiln, which lead to how a microwave kiln works, which lead to heating up a Stirling engine from the inside with microwaves. Basically, turn a microwave kiln into a Stirling engine.
The "hot plate" of the engine would consist of a lining made of silicon carbide, or some similar microwave susceptible material.
The Stirling microwave crucible engine has no outlet for any unused "waste heat". It would, of course, have a heated side lined with silicon carbide to absorb microwaves generating heat, and there would be an unheated side, where no heat would be directly generated, but an "unheated" side is not the same thing as a "sink".
According to Nicola Tesla, and even Carnot speculated in his private journals, that if heat is kinetic energy, there should not be an actual need for any "sink" or cold side.
So, as seemingly impractical as a Stirling engine running inside a microwave oven may be, I think it would be worthwhile as an experiment anyway.
As far as practical applications; what about a spaceship, space station, space telescope etc. powered by a Stirling engine powered by microwave "background radiation" in outer space?
Microwave powered Stirling engine
Re: Microwave powered Stirling engine
The idea was floated here about 9 years ago!
viewtopic.php?t=1673
It doesn't seem it was actually followed up on. Some concern regarding a need for a heat sink was brought up.
I'm of a mind, though, that a sink might actually be unnecessary.
I think some low power, intermittent microwave cycle would more than sufficient. A microwave kiln will heat up enough to melt glass in a matter of seconds.
viewtopic.php?t=1673
It doesn't seem it was actually followed up on. Some concern regarding a need for a heat sink was brought up.
I'm of a mind, though, that a sink might actually be unnecessary.
I think some low power, intermittent microwave cycle would more than sufficient. A microwave kiln will heat up enough to melt glass in a matter of seconds.