[E. Pluribus Unum]

Sounds like an enhanced Sterling engine.

[E. Pluribus Unum]

Stirling

[DUMBGRUNT]

--"Sounds like an enhanced Sterling engine."

Sterling uses heat differential.

This one: Because of its use of a low-temperature reaction without burning or a flame

??? It is some form of internal combustion.
Consuming fuel in a closed chamber.

[Agatsu77]

That’s what I thought. Some sort of sterling engine.