Ultrasonic wave usually contain abundant particle size information when it passes through particulate two-phase flow. With the help of theoretical interpretation

particle size distribution (PSD) can be obtained by extracting effective attenuation and phase velocity spectra. Experiments were carried out to measure the particle size distribution of three kinds of aqueous polystyrene suspension samples with volume fraction of 10%. Attenuation and phase velocity spectra were acquired respectively by double-sample and insert-substitution methods. Furthermore

based on the ECAH model

the Twomey

ORT and an optimization method (Davidon-Fletcher-Powell algorithm) were used to inverse the particle size distribution of suspensions. The ultrasonic measurement results illustrated good consistence with those from microscope image analysis with deviation less than 15%

which indicated that measuring the particle size distribution of suspension with both ultrasonic attenuation and phase velocity spectra was feasible and reliable.