基于COMSOL的油气润滑系统ECT三维阵列电极特性分析∗

摘要

The three⁃dimensional pipe model on Electrical Capacitance Tomography’ s( ECT’ s) array electrodes was built by COMSOL, the potential cloud was obtained under different array electrode structures, the capacitance values of three⁃dimensional electrodes were solved in the case of empty field and full field respectively, and an expression used to calculate quickly sensitivity filed was deduced according to the characteristics of small pipe in oil⁃air lubrication system. The lateral sensitivity and the sensitivity homogeneity were defined and employed to evaluate ECT′s array electrode charac⁃terization of oil⁃air lubrication system, combined with another two traditional assessment index, the sensitivity and the range of measured capacitance values. The results show that the sensitivity of relatively uniform distribution and better de⁃tection sensitivity can be obtained by analyzing characteristics of ECT’ s array electrode. This research provides a basis for design and manufacture of ECT’ s array electrode of the oil⁃air lubrication system.%利用COMSOL有限元软件搭建油气润滑系统电容层析成像（ ECT）的阵列电极三维管道模型，得到阵列电极在不同阵列电极结构参数下的电势云图，并求出空场满场的三维阵列电极的电容值。根据油气润滑系统小管径的管道特点，推导出一种适合油气润滑系统阵列电极三维管道内快速计算灵敏度场的计算表达式；定义横向灵敏性和灵敏度均匀性2个评价指标，并结合传统的阵列电极的灵敏度、被测电容的变化范围2个评价指标对油气润滑系统空间ECT阵列电极进行特性分析。结果表明：经过特性分析的空间ECT阵列电极可获得比较均匀的灵敏度分布和较好的检测灵敏性。该结果将为油气润滑系统ECT阵列电极的后期加工制作提供依据。