Near the critical point, REFPROP 9 may struggle with iteration. If you receive an "iteration limit exceeded" error, switch the input to temperature-density (T,ρ) instead of temperature-pressure (T,p). Density remains single-valued in the two-phase region, even when pressure does not.
NIST REFPROP Version 9 is more than just a calculator; it is a comprehensive database that bridges the gap nist refprop 9
REFPROP 9 is an indispensable tool for:
REFPROP (REference Fluid PROPerties) is a program developed by the National Institute of Standards and Technology (NIST). It calculates the thermodynamic and transport properties of pure fluids and fluid mixtures. Near the critical point, REFPROP 9 may struggle
Version 9.x (released around 2010–2013, with updates like 9.1) is a widely used stable version. It is the last version with a classic Windows interface before major GUI changes in v10. REFPROP 9 is an indispensable tool for: REFPROP