Liquid hydrogen and liquid oxygen propellants require cryogenic property data. REFPROP 9 includes the most recent EOS for ortho-para hydrogen mixtures, which is vital for long-term fuel storage in space missions.
: Calculations for vapor-liquid (VLE), liquid-liquid, and solid-liquid systems. nist refprop 9
| Feature | REFPROP 9 (Legacy) | REFPROP 10 / 10.0 (Current) | | :--- | :--- | :--- | | | ~147 | 200+ (including carbon capture solvents and new low-GWP refrigerants) | | Mixture Model | GERG-2008 (excellent for natural gas) | GERG-2012 (improved for CO2-rich mixtures) | | Transport Properties | Stable, mature correlations | Novel models for ionic liquids and nanorefrigerants | | User Interface | Classic, simple Windows GUI | Modernized with live plotting and tabular exports | | Programming | 32-bit and 64-bit DLL | 64-bit only; Python wrappers improved | | License Cost | No longer for sale (legacy users only) | Active sales; academic discounts available | | Feature | REFPROP 9 (Legacy) | REFPROP 10 / 10
approach rather than separate correlations for individual properties. PubMed Central (PMC) (.gov) REFPROP Documentation - Thermodynamics Research Center And we'll still survive
"When the solar flare hits and the quantum networks fail," he said quietly, "when the AI hallucinates the wrong critical point and everyone forgets how to do a triple-point calculation by hand... we'll still have REFPROP 9. And we'll still survive."