NIST Reference Fluid Thermodynamic and Transport Properties Database (REFPROP) Version 10 - SRD 23

REFPROP is an acronym for REFerence fluid PROPerties. This program, developed
by the National Institute of Standards and Technology (NIST), calculates the
thermodynamic and transport properties of industrially important fluids and their
mixtures. These properties can be displayed in Tables and Plots through the graphical
user interface; they are also accessible through spreadsheets or user-written
applications accessing the REFPROP dll. REFPROP is based on the most accurate pure fluid
and mixture models currently available. It implements three models for the thermodynamic
properties of pure fluids: equations of state explicit in Helmholtz energy, the modified
Benedict-Webb-Rubin equation of state, and an extended corresponding states (ECS) model.
Mixture calculations employ a model that applies mixing rules to the Helmholtz energy of
the mixture components; it uses a departure function to account for the departure from
ideal mixing. Viscosity and thermal conductivity are modeled with either fluid-specific
correlations, an ECS method, or in some cases the friction theory method.