# Multiphase Mixtures

(jl-type-multiphase)=
::::{describe} MultiPhase()
```julia
MultiPhase(phases::AbstractVector{<:Pair{Solution,<:Real}})
```

A mixture of one or more phases.  Construct empty and add phases with
[`add_phase!`](#jl-function-add-phase-bang) followed by [`init!`](#jl-function-init-bang), or pass a vector of
`solution => moles` pairs to add and initialize in one step.

```julia
gas = Solution("gri30.yaml")
mix = MultiPhase([gas => 1.0])
set_temperature!(mix, 1200.0); set_pressure!(mix, one_atm)
equilibrate!(mix, "TP")
```
::::

(jl-function-add-phase-bang)=
::::{describe} add_phase!(mp::MultiPhase, solution::Solution, moles::Real)
Add `solution` to the mixture with the given number of `moles`.  Call
[`init!`](#jl-function-init-bang) after all phases have been added.
::::

(jl-function-init-bang)=
::::{describe} init!(mp::MultiPhase)
Finalize the mixture after all phases have been added.  Required before any
property or equilibrium calculation.
::::

(jl-function-update-phases-bang)=
::::{describe} update_phases!(mp::MultiPhase)
Synchronize the constituent phase objects with the mixture's current state.
::::

(jl-function-n-phases)=
::::{describe} n_phases(mp::MultiPhase)
Number of phases in the mixture.
::::

(jl-function-set-temperature-bang)=
::::{describe} set_temperature!(mp::MultiPhase, T::Real)
Set the mixture temperature [K].
::::

(jl-function-set-pressure-bang)=
::::{describe} set_pressure!(mp::MultiPhase, P::Real)
Set the mixture pressure [Pa].
::::

(jl-function-charge)=
::::{describe} charge(mp::MultiPhase)
Total electric charge [C/mol] of the mixture.
::::

(jl-function-enthalpy)=
::::{describe} enthalpy(mp::MultiPhase)
Total enthalpy [J].
::::

(jl-function-entropy)=
::::{describe} entropy(mp::MultiPhase)
Total entropy [J/K].
::::

(jl-function-gibbs)=
::::{describe} gibbs(mp::MultiPhase)
Total Gibbs free energy [J].
::::

(jl-function-volume)=
::::{describe} volume(mp::MultiPhase)
Total volume [m^3].
::::

(jl-function-phase-moles)=
::::{describe} phase_moles(mp::MultiPhase, n::Integer)
Number of moles in phase `n` (1-based).
::::

(jl-function-set-phase-moles-bang)=
::::{describe} set_phase_moles!(mp::MultiPhase, n::Integer, moles::Real)
Set the number of moles in phase `n` (1-based).
::::

(jl-function-species-moles)=
::::{describe} species_moles(mp::MultiPhase, k::Integer)
Moles of global species `k` (1-based).
::::

(jl-function-element-moles)=
::::{describe} element_moles(mp::MultiPhase, m::Integer)
Moles of element `m` (1-based).
::::

(jl-function-mole-fraction)=
::::{describe} mole_fraction(mp::MultiPhase, k::Integer)
Mole fraction of global species `k` (1-based).
::::

(jl-function-set-moles-bang)=
::::{describe} set_moles!(mp::MultiPhase, moles)
Set the moles of all global species from a numeric vector, or from a
composition string (e.g. `"CH4:1, O2:2"`).
::::