Sound velocities and thermodynamic properties of water to 700 MPa and −10 to 100 °C

Sound velocities in liquid water were measured by the method of impulsive stimulated scattering in a sapphire-windowed high-pressure cell from -10 to 100 degrees C and pressures as high as 700 MPa. Velocity measurements are compared with previous experimental efforts relative to the International Association for the Properties of Water and Steam (IAPWS-95) formulation for the equations of state. At 0 and -10 degrees C, sound velocities are in agreement with the one previously published study at sub-zero temperatures to 350 MPa. At ambient and elevated temperatures, differences between the present measurements and IAPWS-95 velocities approach 0.5% near 700 MPa. Inversion of velocity data for density yields results within IAPWS-95 uncertainties, except at the highest temperatures, where elevated sound velocity at high pressure corresponds to as much as -0.2% disagreement with IAPWS-95.