带有径向电极的小尺度电容层析成像传感器设计

电容层析成像应用于小尺度管道内成像的关键问题是传感器的设计，而常规传感器往往无法满足测量需要。该文在分析小管道测量特点后，提出3种不同径向电极布置的小型电容成像传感器结构，并通过有限元仿真比较了不同径向电极布置对测量电容的影响。同时，对电极间绝缘介质介电常数及屏蔽罩与电极外表面距离对电极对间电容的影响进行了详细地探讨。结果表明，对于具有较厚厚度的电极，电极对间的本体电容主要来自电极对侧表面间的电容，且相邻电极间绝缘介质介电常数对电极对间电容的影响不显著，但电极对间电容随着屏蔽罩与电极外表面距离增加而增加。依据仿真结果，设计出一种新型径向电极布置的小尺度传感器，并将其用于实测，获得了较好的结果。

Design for Miniature Electrical Capacitance Tomography Sensor With Radial Screens

Sensor design is the key to miniature electrical capacitance tomography.Three types of miniature sensors with radial screens were proposed.The effects of the three types of radial screens,the dielectric permittivity of the material between two adjacent electrodes,and the distance between outer screen and electrodes on capacitances were analyzed in detail by the method of finite element simulation.The simulation results show that the standing capacitances of the thick electrodes arise mainly from the lateral,and the dielectric permittivity of the material between two adjacent electrodes has less effect on the capacitances,while the capacitances increase with the distance between outer shield and electrodes.According to the simulation results,a novel miniature-sensor with radial screens was designed and tested,and good results were obtained.