EntropyScaling.jl

Transport property modeling based on entropy scaling and equations of state (EOS).

This package provides models for

• the viscosity,
• the thermal conductivity, and
• diffusion coefficients.

The documentation of the package can be found here.

For the EOS calculations, additional packages need to be imported. Alternatively, custom EOS functions might be defined. Implementations of EOS models are not included in this package.

Installation

The package can be installed by:

Pkg> add EntropyScaling

Package mode can reached by typing ] in REPL. Then, the module can be loaded by

using EntropyScaling

Examples

Chapman-Enskog viscosity (zero-density limit) of methane

julia> using EntropyScaling

julia> model = ChapmanEnskog("methane")
ChapmanEnskogModel{methane}
 σ: [3.758] Å
 ε: [148.6] K
 M: [0.01604] kg/m³
 Collision integral: KimMonroe

julia> η = viscosity(model, NaN, 300.)      # gas viscosity of methane at 300 K in Pa s
1.1189976373570321e-5

Fitting a new entropy scaling model

julia> using EntropyScaling, Clapeyron

julia> (T_exp,ϱ_exp,η_exp) = EntropyScaling.load_sample_data();    # Load sample data
┌ Info: Experimental data for the viscosity of n-butane.
└       Units: [T] = K, [ϱ] = mol/m³, [η] = Pa·s

julia> data = ViscosityData(T_exp, [], ϱ_exp, η_exp, :unknown)
TransportPropertyData{Viscosity}
    15 data points.

julia> eos_model = PCSAFT("butane")                     # Clapeyron.jl EOS model
PCSAFT{BasicIdeal, Float64} with 1 component:
 "butane"
Contains parameters: Mw, segment, sigma, epsilon, epsilon_assoc, bondvol

julia> model = FrameworkModel(eos_model, [data])        # Fit model parameters
FrameworkModel with 1 component:
 "butane"
 Available properties: viscosity
 Equation of state: Clapeyron.EoSVectorParam{PCSAFT{BasicIdeal, Float64}}("butane")

julia> η = viscosity(model, 1e5, 300.; phase=:liquid)   # viscostiy at p=1 bar and T=300 K
0.0001605897169488518

Integration with Unitful.jl

It is possible to work woth units using Unitful.jl. The following example uses the model from above, but calculates the viscosity with units.

julia> using Unitful

julia> η = viscosity(model, 1u"bar", 26.85u"°C", phase=:liquid, output = u"cP")
0.16058971694885213 cP