The equation of state of pure water determined from sound speeds

Abstract

The equation of state of water valid over the range 0–100 °C and 0–1000 bar has been determined from the high pressure sound velocities of Wilson, which were reanalyzed by Chen and Millero. The equation of state has a maximum error of ±0.01 bar⁻¹ in isothermal compressibility and is in the form of a secant bulk modulus: K=V⁰P/(V⁰−V) =K⁰+AP+BP², where K, K⁰, and V, V⁰ are the secant bulk moduli and specific volumes at applied pressures P and 0 (1 atm), respectively; A and B are temperature dependent parameters. The good agreement (to within 20×10⁻⁶ cm³ g⁻¹) of specific volumes calculated using the above equation with those obtained from other modifications of the Wilson sound velocity data demonstrates the reliability of the sound velocity method for determining equations of state.