超声衰减法测量油水分散流中颗粒粒度分布

Measurement of Particle Size Distribution in Dispersed Oil-Water Two-Phase Flow Using Ultrasonic Attenuation Method

针对油水分散流的颗粒粒度测量问题,提出一种基于多频率下超声衰减作用的测量方法。根据多相流体中超声衰减的BLBL模型,推导出超声衰减系数与颗粒粒度分布存在的数学表达关系。通过多频率条件下所获得的超声衰减系数进行联合比较分析,求解被测流体中颗粒粒度分布.通过对含油率低于30%的5个样本中4种颗粒粒度分布的油水分散流进行数值模拟仿真实验,得到颗粒粒度占比分布的测量结果,并对结果进行分析,得到BLBL模型在毫米尺度油相颗粒作为离散相的油水分散流中的适用条件和范围。

For the measurement of discrete particle size in dispersed oil-water two-phase flow, a measurement method based on ultrasonic attenuation with multi-frequency was proposed. According to the BLBL （Bouguer-Lambert-Beer-Law） model of ultrasonic attenuation, the relationship between the ultrasonic attenuation coefficient and the particle size distributions were derived. By analyzing the ultrasonic attenuation coefficient got from multi-frequency, the particle size distributions in the measured flow were obtained. Numerical simulations covered 4 types of diameters of droplets in oil-water dispersion flow at 5 flow conditions of oil fraction under 30%. The particle size distributions were analyzed to conclude the feasible condition and range of BLBL model in millimeter-scale oil droplets of the dispersed oil-water two-phase flow.