With Version 10 and 11 available, why the interest in 9.1?
REFPROP, developed by the National Institute of Standards and Technology (NIST), is a comprehensive software package that provides detailed property data for refrigerants, including thermodynamic properties, transport properties, and phase equilibrium data. It's essential for engineers and researchers working with fluid dynamics, HVAC (heating, ventilation, and air conditioning), refrigeration, and chemical engineering.
Released in the early 2010s, REFPROP 9.1 was a significant update. It included:
The current version (10.0 or 11.0) has more features, but 9.1 remains popular because older hardware can run it and legacy tutorials reference it. refprop 91 free
If you need "refprop 91 free" functionality for a class project or personal research, follow this workflow:
Step 1: Go to coolprop.org/downloads/
Step 2: Download the "CoolProp for Windows (Standalone GUI)." This is an .exe file that looks and feels similar to REFPROP’s interface.
Step 3: Install it (no admin rights needed, no malware).
Step 4: Select a fluid – say, "Water" or "R134a."
Step 5: Input temperature and pressure. CoolProp returns density, enthalpy, entropy, viscosity, and thermal conductivity.
Step 6 (Advanced): For mixtures, use the Python interface: from CoolProp.CoolProp import PropsSI and PropsSI('H','T',300,'P',101325,'R32&R125')
Result: You get REFPROP-level accuracy, no license file, no crack, and no FBI warning. With Version 10 and 11 available, why the interest in 9
NIST no longer sells version 9.1 — they sell version 10.0 (2023). To use REFPROP legitimately:
Many universities and educational institutions have site licenses. If you are a student or a professor, you likely have access to REFPROP through your university’s software portal at no cost to you personally. Check with your IT department or engineering library before attempting to find unauthorized versions online.
In the world of chemical engineering, HVAC design, and cryogenics, few tools are as revered as NIST REFPROP (Reference Fluid Thermodynamic and Transport Properties Database). Developed by the National Institute of Standards and Technology (NIST), REFPROP is the industry standard for calculating the properties of pure fluids and mixtures. The current version (10
Version 9.1 (REFPROP 9.1) is a specific release that many users search for, hoping to find a "free" copy. The search term "refprop 91 free" is searched thousands of times monthly by students, engineers, and hobbyists who cannot afford the commercial license.
But does a legitimate, free version of REFPROP 9.1 exist? And if you find a download link, should you use it?