The publications that this code is based on are listed under references. If you use this code, make sure to cite these publications accordingly. These papers also contain further information on equations, such as the validity range.

Phase boundaries and virial coefficients as a function of temperature in K
melting pressure pMelt in MPa
sublimation pressure pSub in MPa
vapor pressure pVap in MPa
saturated liquid density rhoLiqSat in kg/m^3
saturated vapor density rhoVapSat in kg/m^3
second virial coefficient B in m^3/kg
third virial coefficient C in (m^3/kg)^2
Phase boundary functions return nan outside their validity range. The validity range is not checked for the virial coefficients.

Equilibrium properties can be calculated in two ways:
1) as a function of density in kg/m^3 and temperature in K
e.g. entropy = CO2.s_rhoT(density, temperature)
2) as a function of pressure in MPa and temperature in K
e.g. entropy = CO2.s_pT(pressure, temperature)
The inputs must have the same size or one of them has to be a scalar.

Equilibrium properties:
pressure p in MPa
density rho in kg/m^3
entropy s in kJ/(kg K)
internal energy u in kJ/kg
isochoric heat capacity cv in kJ/(kg K)
enthalpy h in kJ/kg
isobaric heat capacity cp in kJ/(kg K)
saturated liquid heat capacity cs in kJ/(kg K)
speed of sound w in m/s
Joule-Thomson coefficient mu in K/MPa
fugacity coefficient f

Transport properties have to be calculated both at once, since they depend on each other in the critical region. Just as with equilibrium properties, they can be calculated in two ways:
1) as function of density in kg/m3 and temperature in K
[mu, lambda] = CO2.transport_rhoT(density, temperature)
2) as a function of pressure in MPa and temperature in K
[mu, lambda] = CO2.transport_pT(pressure, temperature)

Transport properties:
viscosity mu in mPa s
thermal conductivity lambda in mW/(m K)

+++ References +++

Equation of State/Equilibrium properties
R. Span and W. Wagner (1994): A New Equation of State for Carbon Dioxide Covering the Fluid Region from the Triple-Point Temperature to 1100 K at Pressures up to 800 MPa. In J. Phys. Chem. Ref. Data, Vol. 25, No. 6
DOI: https://doi.org/10.1063/1.555991

Transport properties
M. L. Huber, E. A. Sykioti, M. J. Assael and R. A. Perkins (2016): Reference Correlation of the Thermal Conductivity of Carbon Dioxide from the Triple Point to 1100 K and up to 200 MPa. In J. Phys. Chem. Ref. Data, Vol. 45, No. 1
DOI: https://doi.org/10.1063/1.4940892

A. Laesecke and C. D. Muzny (2017): Reference Correlation for the Viscosity of Carbon Dioxide. In J. Phys. Chem. Ref. Data, Vol. 46, No. 1
DOI: https://doi.org/10.1063/1.4977429

J. Luettmer-Strathmann, J. V. Sengers and G. A. Olchowy (1995): Non-asymptotic critical behavior of the transport properties of fluids. In J. Chem. Phys. 103 (17)
DOI: https://doi.org/10.1063/1.470718

Transport properties (depreciated)
V. Vesovic, W. A. Wakeham, G. A. Olchowy, J. V. Sengers, J. T. R. Watson and J. Millat (1990): The Transport Properties of Carbon Dioxide. In J. Phys. Chem. Ref. Data, Vol. 19, No. 3
DOI: https://doi.org/10.1063/1.555875

A. Fenghour, W. A. Wakeham and V. Vesovic (1997): The Viscosity of Carbon Dioxide. In J. Phys. Chem. Ref. Data, Vol. 27, No. 1
DOI: https://doi.org/10.1063/1.556013