Liquid piston Stirling engines (Fluidyne)

[justincorhad]

Would it be possible to make a liquid piston Stirling engine that was not open to atmosphere? Could it not have a sealed working fluid like a conventional Stirling? Surely it should act the same way yes?

[mmattil]

From what I have seen many Fluidyne style engines still use air as the working fluid. Are you talking about replacing all of the working fluid with a liquid or just capping the atmospheric end of the liquid piston but still using air (or a gas) as the working fluid?

[Bumpkin]

I would think that closing a fluidine from atmosphere to raise it’s working pressure might have the same benefits as with other Stirlings, except that liquid piston engines are generally (exclusively?) used for water pumping and the internal pressure might offset the pumping process. If you got this far you’re probably ahead of that and maybe have an answer? An interesting idea/question.
Bumpkin