I'm just getting into how it all works.
Can someone please say, can the displacement piston be made out of a
porous material needed so that it double duties as a regenerator such
that the gas goes through it and it absorbs some of the heat and then
gives it back when the gas goes the other way? If not why not?
I mean can I pack a hollow cylinder with the regen material dense
enough that it provides the same gas flow as goes through the