摘要
基于静电传感器空间滤波技术的气固两相流颗粒速度测量方法具有结构简单、数据处理方便等特点。文中从理论上推导了圆环状静电传感器输出信号的功率谱特性与颗粒移动速度之间的关系，并对电极长度、绝缘管段的厚度和屏蔽罩轴向长度等因素对静电传感器空间滤波特性的影响进行了仿真分析，为静电感应空间滤波器的设计提供了理论基础。提出利用小波分析对功率谱特性曲线进行平滑处理的方法，可准确地确定功率谱特性曲线的尖峰频率值fmax。并在加压密相气力输送系统上进行实验研究，结果表明：颗粒体积浓度范围在6．72％～13．04％，气体表观速度在8．63～18．61m／s之间时，系统重复性优于4％。
Electrostatic induction based spatial filtering technique for solid particle velocity measurement has the advantages of the simplicity of measurement system and the convenience of data processing. The relationship between the solid particle velocity and the power spectrum of output signal of the electrostatic senor was derived theoretically. And the effects of the length of the electrode, the thickness of the dielectric pipe and the length of the mental screen on the spatial filtering property of the sensor were investigated numerically using finite element method. Additionally, as for the roughness of the power spectrum characteristics curve of the output signal and the difficult determination of peak frequency fmax, a wavelet analysis based filtering method was adopted to smooth the curve, which can determine peak frequency fmax accurately. Finally, the velocity measurement method was applied to a dense phase pneumatic conveying system under high pressure, and the experimental results show that the system repeatabifity is within ±4% over the gas superficial velocity range of 8.63-18.61m/s for particle concentration range 6.72%-13.04%.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2007年第26期84-89,共6页
Proceedings of the CSEE
基金
国家重点基础研究专项经费资助项目(2004CB1770204)~~
关键词
颗粒速度
空间滤波法
静电传感器
小波分析
气固两相流
particle velocity
spatial filtering method
electrostatic sensor
wavelet analysis
gas-solid two phases flows
