Does the isoenthalpic-isobaric ensemble (also called the NPH ensemble) represent a system capable of exchanging only pressure-volume work with a barostat, but no heat with a heat bath or particles with a reservoir? And if not, what would be a name (and the "acronym") for such ensemble?
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If $N,P,H=const.$, we have
$$dH = \delta Q - VdP + \mu dN = \delta Q = 0$$
since both $dH$, $dP$ and $dN$ are zero. This means indeed that the system does not exchange heat, but only isobaric work with the reservoir:
$$dU = -P dV$$
In some way, we can think of our system as an adiabatic, impermeable "balloon" of variable volume in a constant-pressure environment.