nH2O is a “water property” calculator that calculates various thermodynamic properties of steam and water. nH2O is based upon the Modular Modeling System (MMS) steam property library which is composed of a set of routines, some polynomials and some table interpolations of the thermodynamic properties of steam and water. In general, all subcooled liquid and superheated vapor of steam properties are accurate to +/- 0.24% within a pressure range of 0.01 to 6,000 psia and enthalpy ranges from 100 btu/lbm to 1600 btu/lbm outside the saturation region. Saturated properties are accurate to within +/- 0.24% from 0.1 psia to 3,200 psia within the saturated region.

The Calculator calculates:

Saturation Properties as a function of Pressure (P)
Saturation Properties as a function of Temperature (T)
Subcooled, Saturation, Superheated properties as a function of Pressure & Enthalpy (PH)
Subcooled, Saturation, Superheated properties as a function of Pressure & Temperature (PT)

Calculated properties include Pressure (P), Temperature (T), Enthalpy (h), Entropy (s), Specific Volume (v), Density (ρ), and Quality (x).

Support is provided for both US Conventional units, and Conventional SI units.

Note: The functions used in the nH2O calculator are adapted from the MMS steam property library which is designed for dynamic thermodynamic simulation. As such, they were optimized for speed of calculation. The results are generally comparable (within tolerances mentioned above) to conventional steam property routines, but keep in mind that they will not be identical to ASME, IAPWS, or IFC formulations.