Speed of Sound in Liquid Water from (253.15 to 348.15) K and Pressures from (0.1 to 700) MPa

Water thermodynamic properties are available as standards through the IAPWS-95 formulation of the equation of state. Among these properties, speed of sound is very useful for calibrating devices and for obtaining derived properties. However, the values of speed of sound calculated in the range (200 to 700) MPa are more uncertain than desirable, due to a lack of accurate experimental data above 200 MPa. The aim of this work is to provide a complete set of accurate speed of sound results in water covering the pressure range mentioned above. Speed of sound was determined by the multiple reflections method between (0.1 and 700) MPa at temperatures from (253.15 to 348.15) K. Estimated uncertainties at a confidence level of 95 % range between (0.22 and 0.32) % over the whole pressure range. These new results may help to improve the reference database for future parametrizations of the equation of state for water.