Ultrasonic propagation studies in suspension systems

Abstract

The fluctuations occurring in the ultrasonic wavefronts propagating through inhomogeneous media are identified as a source of artefacts in measuring speed, attenuation and scattering in such media. An experimental system for making such measurements using a scanned hydrophone is described. Results are presented of amplitude and phase measurements of suspensions of glass beads in silicone rubber for mean bead diameters between 100 and 550 mu m and concentrated by weight from 0 to 17.2%. The amplitude and phase fluctuations are observed to increase together. The absence of a relevant theoretical basis for interpretation of the results presented is discussed.