Compressional Viscosity and Sound Absorption in Water at Different Temperatures

Abstract

The temperature dependence of the coefficient of absorption ($2\alpha {\nu }^{-2\mathrm{}}$) of ultrasonic waves in water was measured from 0°C to 33°C. Values range from 137×${10}^{-17\mathrm{}}$ at 0°C to 40×${10}^{-17\mathrm{}}$ at 33°C. In particular at 4°C where the sound propagation is isothermal the value 101×${10}^{-17\mathrm{}}$ is found, and is to be compared with a shear viscosity contribution of 30×${10}^{-17\mathrm{}}$. Therefore the excess cannot be caused by the slowness of energy exchange between the internal and external degrees of freedom. The excess absorption is used to calculate the value of a new coefficient of compressional viscosity $k$, which is found to be 0.052 poise at 4°C and 0.026 poise at 20°C. A general discussion of the origin of sound absorption in liquids is included, with particular applications to recent measurements.