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NIST Standard Reference Database 23 - NIST Thermodynamic and Transport Properties REFPROP, Version 7.0



Eric W. Lemmon, Mark O. McLinden, Marcia L. Huber


Knowledge of the thermophysical properties is essential for the evaluation of alternative refrigerants and the design of equipment using them. The REFPROP computer database from the National Institute of Standards and Technology has been one of the more widely used tools designed to provide these data. In the initial versions of REFPROP (Gallagher et al. 1993), the intent was to provide data on a wide variety of fluids to allow screening studies of possible replacements for the CFC or HCFC refrigerants. For many of these fluids, only sparse data were available, and onsequently, the database relied primarily on a simple model with few adjustable parameters, i.e., the Carnahan-Starling-DeSantis (CSD) equation of state. As the alternative refrigerants move from the laboratory to use in commercial equipment, more complete property data are required for a more limited set of fluids.This seventh version of REFPROP is a complete revision based on the most accurate pure fluid and mixture models currently available. It implements three models for the thermodynamic properties of pure fluids: the modified Benedict-Webb-Rubin equation of state, the Helmholtz-energy equation of state, and an extended corresponding states (ECS) model. It uses a departure function to account for the departure from ideal mixing. Viscosity and thermal conductivity are modelled with either fluid-specific correlations or an ECS method.
World Wide Web-Internet and Web Information Systems
Version 7.0


alternative refrigerants, ammonia, CFC, chemical engineering, chlorofluorocarbons, equation of state, hydrofluorocarbons, refrigerants, thermodynamics


Lemmon, E. , McLinden, M. and Huber, M. (2002), NIST Standard Reference Database 23 - NIST Thermodynamic and Transport Properties REFPROP, Version 7.0, World Wide Web-Internet and Web Information Systems (Accessed July 18, 2024)


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Created July 1, 2002, Updated June 2, 2021