Sorry if this question is a bit dumb...
I think (but correct me if I'm wrong) that ice cream moving in a perfect ice cream maker is an example of ergodic flow: the flow itself is conserved, no molecule of the mixture remains in the same place (during a complete turn of the palette at least), there are no subset orbits, and if we wait for a long enough time a molecule will visit the same place twice (for some discretized notion of "place" perhaps).
I also think that boiling water is not ergodic, if we use the same definition of flow (the molecules in the boiling water) and of "place", because some molecules are escaping all the time as vapor.
Question: Am I roughly correct, or roughly wrong? Do I need to revise my examples in some other way?
Thanks in advance.