基于平面电容的油水多界面检测方法研究

含水量是衡量原油质量的重要指标，在原油的生产和储运过程中油水混合液分界面不断变化，因此全过程都要用到高精度传感器对其进行界面检测。基于电容边缘效应设计了一种侵入式平面电容传感器，其主要结构由基板和平面电极阵列两部分组成。运用有限元软件建立8电极阵列传感器模型，对不同电极工作时的电场分布进行研究，分析了平面电容传感器的检测灵敏度和成像精度。并且，研究了电极宽度、长度和相邻间距对传感器灵敏场分布的影响。对介电分布进行图像重建，使设计的平面电容阵列传感器可以检测3个分界面的高度，且经过尺寸参数优化，提高了传感器的成像精度。实验证明，运用平面电容阵列检测油水界面的方法具有可行性和有效性。

Study on detection method of oil-water multi-interface based on planar capacitance

Water content is an important indicator to measure the quality of crude oil. In the process of production, storage and transportation of crude oil, the interface of oil-water mixture is constantly changing. Thus, high-precision sensors are used to detect it in the whole process. In this article, an intrusive planar capacitance sensor was designed based on the capacitive edge effect. Its main structure consists of a substrate and a planar electrode array. The 8-electrode array sensor model was established by using finite element software. The electric field distribution of different electrodes was studied, and the detection sensitivity and imaging accuracy of the planar capacitive sensor were analyzed. In addition, the influence of the width, length and adjacent distance of the electrodes on the sensitive field distribution of the sensor was studied. Through the image reconstruction of the dielectric distribution, the designed planar capacitance array sensor can detect the height of the three interfaces, and the size parameters are optimized to improve the imaging accuracy of the sensor. The feasibility and effectiveness of the method of using planar capacitor array to detect oil-water interface have proved by experiments.