Application of multiple scattering theories to the evaluation of granular distributions based on phase velocity measurements

Using multiple scattering theories, the influence of granular distribution on acoustic phase velocity in particle-loaded liquids was studied. Theoretical results were compared to measurements in suspensions of acrylic spheres in ethylene glycol. It appears that the phase velocity versus frequency shows a minimum, the position and sharpness of which are related to the mean diameter of particles and to the standard deviation of the diameter distribution. Its amplitude is only influenced by the concentration. Therefore, it is shown that granulometric properties of suspensions can be determined by an ultrasonic method, through the behavior of phase velocity versus frequency.