REFPROP 9.1 is a proprietary software developed by the National Institute of Standards and Technology (NIST) and is not officially available for free. It is a high-accuracy computational tool used to calculate the thermophysical properties of industrially important fluids and their mixtures. 1. Official Free Version (REFPROP Mini)
- REFPROP 9.1 is a commercial product developed by the National Institute of Standards and Technology (NIST).
- Searching for “refprop 91 free” typically leads to:
Quick comparison (high level)
- REFPROP 9.1: very high accuracy, broad refrigerant/mixture support, proprietary.
- CoolProp: free/open, good accuracy for many fluids, active community.
- IAPWS: authoritative for water/steam only.
- Commercial packages: can match/refine REFPROP capabilities but cost money.
The Technical Significance of REFPROP 9.1
Limitations: It typically includes only a limited selection of fluids (like water, air, and some refrigerants) and fewer calculation features compared to the full database.