Ph for known to be two-phase mixtures

[ianhbell]

See implementation in Gernert

[ianhbell]

Imagine two phases in a vessel in equilibrium, they are in thermal and mechanical equilibrium so at the same pressure and temperature, which is why you get the formulation in Gernert. It is not entirely obvious at first.

[ianhbell]

There are four terms that need to be included in the derivative: h', h'', and beta. Working variables are molar concentrations and temperature.

[ianhbell]

This is almost done, generalized treatment derived and implemented