超声波在颗粒两相体系中传播,包含了大量颗粒粒径信息,结合理论模型,通过提取超声波有效衰减谱和相速度谱分析了颗粒的粒径分布。实验中,对体积分数为10%的3种不同粒径分布的聚苯乙烯-水悬浊液,通过双样法和插入取代法(单样法)分别获得宽带超声波衰减谱与相速度谱,以ECAH模型为理论基础,并分别用Twomey、ORT和Davidon-Fletcher-Powell优化算法,反演出悬浊液颗粒粒径分布。测量结果与显微镜图像法结果进行对比,中位径误差小于15%,表明了利用超声波衰减谱法(UASA)和相速度谱法(UPVSA)测量悬浊液颗粒粒径分布的可行性与可靠性。
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.