基于静电与声发射传感器的气送颗粒截面分布测量

Cross-sectional distribution measurement of pneumatically conveyed particles using electrostatic and acoustic emission sensors

通过气力管道输送固相物料颗粒的方式广泛存在于工业生产过程中。在大尺度气力输送管道中,颗粒流动状态复杂且分布不均,为精确表征管道内颗粒的流动状态,提出一种融合静电传感器和声发射传感器信息的气送颗粒参数分布测量方法。为了获得颗粒在管道横截面上局部参数信息,将边长为200 mm的方形管道横截面均分为16个静电测量区域和4个声发射测量区域。在30组不同的输送速度和质量流量条件下开展实验研究。结果表明,大尺度方形管道横截面上固相颗粒参数分布不均匀,速度分布情况符合渐扩管道流动规律。结合局部颗粒速度分析质量流量分布的测量结果,发现静电信号与声发射信号的均方根值所表征的颗粒相对质量流量分布变化趋势相同。

Conveying solid particles through pneumatic pipes is widely used in various industrial processes.In large-scale pneumatic conveying pipelines,the particles are unevenly distributed in the pipeline and the particle flow state is complex.To accurately characterize the flow parameters of the particles in the pipeline,this article proposes a measurement method integrating the electrostatic and acoustic emission sensors.To obtain the velocity and relative volumetric distribution of particles in localized areas on the pipe cross-section,the cross-section of the square-shaped pipe with a side width of 200 mm is divided into 16 electrostatic signal sensing zones and 4 acoustic emission signal measurement areas.Experimental tests are conducted under 30 different conditions with various particle velocities and mass flow rates.Experimental results show that the particle distribution is inhomogeneous in the large-scale square pipe cross-section,and the velocity distribution is consistent with the characteristics of the asymptotic pipeline flow.Based on the analysis of mass flow rate distribution considering the local particle velocities,the relative mass flow rate distributions of the particles represented by the RMS values of electrostatic and acoustic emission signals vary in the same trend.