基于静电法的气力输送局部流动特性R/S分析  

R/S analysis for local flow characteristics of pneumatically conveyed particles using electrostatic method

作　　者：王超[1] 张靖宇[1] 张一顺[1] 丁红兵[1] 

机构地区：[1]天津大学电气与自动化工程学院,天津300072

出　　处：《中南大学学报（自然科学版）》2016年第5期1794-1798,共5页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(61072101)~~

摘　　要：利用静电电极的局部敏感特性,使用四电极静电传感器对气力输送过程中管道截面局部流动状态进行研究,运用R/S法提取颗粒运动微观特征。研究结果表明:当表观气速上升,静电信号Hurst指数随之下降,颗粒运动复杂度升高,Hurst指数对输送气速变化引起的颗粒运动状态改变具有很好的表征效果。在水平管道截面内,上侧区域静电信号Hurst指数远比左侧、右侧及下侧区域的高,说明上侧区域颗粒运动复杂度较低。当管内流型发生变化时,下侧区域静电信号Hurst指数的相对变化最明显,可以反映颗粒沉积过程。R/S分析法为气力输送流型的研究提供了一种有效的判断方法。A four-electrode electrostatic sensor with local electrostatic sensibility was used for studying local flow characteristics in the pneumatic conveying process. Moreover R/S method was adopted to characterize the complexity of particle motion. The results show that the Hurst exponent of electrostatic signal has a decreasing trend with the increase of surficial gas velocity, which indicates that the complexity of particle motion increases. Thus the Hurst exponent can represent the particle motion state when the conveying velocity changes. In the horizontal pipe, the Hurst exponent of the electrostatic signal in the top of the pipe is higher than those in other regions. It is demonstrated that the particle motion in the top of the pipe is with low complexity. When the flow pattern changes, the Hurst exponent of the electrostatic signal in the bottom of the pipe changes clearly, which shows the particle deposition. The R/S method is an effective judgment for flow pattern of pneumatic conveying.

关 键 词：静电传感器 气力输送 流动特性 R/S分析 

分 类 号：TB971[一般工业技术—计量学]