Peng-Robinson + MHV1 (Gᴱ mixing) property package

Cubic EoS whose a_mix comes from NRTL's excess Gibbs energy instead of a kij — the package for polar / hydrogen-bonding mixtures AT PRESSURE (alcohol-water, water-amine), where a kij cannot describe the non-ideality and an activity model cannot handle a supercritical component. MHV1 matches Gᴱ at zero pressure, so the solver's existing low-pressure NRTL binaries are the correct parameters with no refit.

Flowsheets that use it