Abstract: In order to study the influence of continuous and pulsed wave excitations on particle size characterization, two experimental systems based on the waves have been established, and variable sound path method is adopted during the measurement to obtain the acoustic attenuation of SiC suspension with two immersion transducers at four different mass concentrations (14%, 17%, 20%, 25%) under the same experimental condition. It is shown that the results have the same tendency obtained with the two systems. The acoustic attenuation under continuous wave excitation is 10% larger than that of pulsed one in value due to the interference. It is found that the deviation of particle size distribution of SiC obtained with the inversion algorithm under the two different excitation modes is within 5%, which indicates that there is a little influence of different excitation modes on particle size characterization.

Key words: continuous wave, pulsed wave, ultrasound, particle size, measurement

摘要： 为了研究连续和脉冲超声波2种不同激励方式对颗粒粒度表征的影响，设计了2套分别基于连续和脉冲超声波对颗粒粒度表征的实验系统，在相同实验条件下，利用一对水浸式探头构成一发一收的模式，采用变声程法，对4种不同浓度的SiC悬浊液声衰减谱进行测量. 结果表明，2套系统所测的声衰减谱趋势相同，连续波激励下的声衰减谱数值偏大10%左右. 结合反演算法得出了SiC微粉颗粒的粒度分布，发现不同激励方式下的颗粒粒度分布吻合程度较好，偏差均在5%以内，说明不同激励方式对颗粒粒度表征最终结果影响不大.

关键词: 连续波, 脉冲波, 超声, 颗粒粒度, 测量