纵向多极电导传感器频率响应特性

FREQUENCY CHARACTERISTICS OF VERTICAL MULTI-ELECTRODE CONDUCTANCE SENSOR

研究了电导传感器空间灵敏度分布，定量分析了传感器空间滤波特性，在此基础上推导了电导传感器频率响应特性函数：结果表明：存空间频域和时间频域内，电导传感器均相当于一个低通滤波器．而且径向位置越小，频带越窄；测量电极间距越小，频带越宽一油泡移动速度对传感器时域频率特性有较大影响，移动速度越快，时域频带越宽：此外，油泡在管道截面上分布不同时，电导传感器输出信号的频率特性可看作是各径向位置上传感器输出信号频率特性的叠加。

This paper studies spatial sensitivity distribution of vertical multi-electrode conductance sensor, quantitatively analyzes its spatial filtering property, and derives frequency response characteristic function of the conductance sensor. Results indicate that conductance sensor acts as a low-pass filter in spatial and temporal frequency domains. The smaller the radial position is, the narrower the frequency bandwidth is; the smaller the distance of measured electrodes is, the wider the frequency bandwidth is. Oil-bubble＇ s moving velocity has much effect on temporal frequency response characteristics of sensors. The faster the moving velocity is, the wider the temporal bandwidth is. Additionally, frequency response characteristics of output signals from conductance sensors can be taken as the superimposition of frequency response characteristics of output signals from conductance sensors on each radial position when distribution of oil-bubbles in the cross section of a pipe is different.