REFPROP

{{Short description|Fluid property prediction software}}

{{Infobox software

| name = REFPROP

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| developer = National Institute of Standards and Technology (NIST)

| released = {{start date and age|1989}}

| latest release version = 10.0

| latest release date = 2018

| programming language = Fortran

| platform = x86-64

| language = English

| genre = Thermophysical property software

| license = Proprietary

| website = {{URL|https://www.nist.gov/srd/refprop}}

}}

REFPROP is a software program for the prediction of thermophysical properties of fluids, developed by the National Institute of Standards and Technology (NIST).{{cite journal | last1=Huber | first1=Marcia L. | last2=Lemmon | first2=Eric W. | last3=Bell | first3=Ian H. | last4=McLinden | first4=Mark O. | title=The NIST REFPROP Database for Highly Accurate Properties of Industrially Important Fluids | journal=Industrial & Engineering Chemistry Research | volume=61 | issue=42 | date=2022-10-26 | issn=0888-5885 | pmid=36329835 | pmc=9619405 | doi=10.1021/acs.iecr.2c01427 | doi-access=free | pages=15449–15472 }}{{cite book | last1=Reynolds | first1=William C. | last2=Colonna | first2=Piero | title=Thermodynamics | publisher=Cambridge University Press | publication-place=New York, NY, USA | date=2018-09-20 | isbn=978-0-521-86273-8}}{{cite book | last=Penoncello | first=Steven G. | title=Thermal Energy Systems | publisher=CRC Press | date=2018-09-19 | isbn=978-1-351-73657-2 | page=}}

The primary component of REFPROP is an equation of state for each implemented fluid. For most pure fluids, the equation of state is obtained by fitting an expression for the Helmholtz free energy to experimental data. This formulation allows the computation of all equilibrium properties of the fluid, such as density, temperature, pressure, sound speed, heat capacity, second virial coefficients, vapor pressures, saturated liquid and vapor densities, enthalpy of vaporization, entropy, and the Joule-Thomson coefficient.

REFPROP also predicts surface tension, viscosity, and thermal conductivity for many fluids, either using extended corresponding states formulations or fluid-specific equations fit directly to experimental data.

Various methods are used to compute the analogous properties of fluid mixtures.

The full list of fluids properties implemented in REFPROP v10.0 can be found in Table 2 of Huber, et al. (2022).