插入式静电传感器特性研究

Study on the Characteristics of Electrostatic Sensor Inserted into Pipes

插入式静电传感器在测量气一固两相流参数和保证其传送安全方面有较好的应用。通过建立电极数学模型，讨论了插入式静电传感器电极的插入深度、空间滤波特性和空间灵敏度特性，得到固体颗粒位置对电极上感应电荷的影响情况、感应电极灵敏度分布规律和插入深度L与电极测量信号幅值之间关系。对于连续流动的固相颗粒，当插入式电极插入深度￡为管道直径的1／2时为最佳尺寸，此时电极具有低通滤波特性。在利用电极数学模型对电极空间滤波特性理论推导的过程中获得了固相颗粒速度与测量信号截止频率的表达式。实测结果证实了电极的空间滤波特性和空间灵敏度特性。

The electrostatic sensor inserted into pipes is successfully applied for measuring the parameters of the gassolid two phase flow and ensuring the safety during the gas-solid two phase flow convey. Through establishing the mathematical model of the probe, the inserted depths, spatial filter characteristics and the spatial sensitivity characteristics of the inserted probe are discussed. The situation which the particles position effect on the induced charges of the probe, and the relation between the inserted depth of probe and the signal amplitude measured are obtained. For the continuous flow of solid particles inserted probe,the optimum inserted depth is 1/2 of the pipe diameter and the probe has low-pass filter characteristic. The expression about the solid particle velocity and the measured signal cut-off frequency is obtained during deducing spatial filter characteristic of the probe with probe mathematics model. The measured results confirm the spatial filter characteristic and spatial sensitivity characteristic of the probe.