A Pulse Method for the Measurement of Ultrasonic Absorption in Liquids: Results for Water

Abstract

It is well known that measurements of the absorption of ultrasonic waves in liquids^1–3 often do not show good agreement, and that for numerous liquids they indicate absorption coefficients many times those calculated on the assumption of a purely viscous loss. Because of these discrepancies it was considered useful to make measurements by a new technique, and one was chosen which would remove many of the possible objections to previous methods. A ‘radar pulse’ technique was developed, in which a short wave-train was emitted in a narrow pencil from a quartz oscillator; the sound, after travelling through the liquid, was reflected and received by the same quartz plate, which thus acted as a common ‘transmit–receive’ transducer.