基于电-声复合传感器测量含水合物液膜厚度仿真研究

针对天然气输送管道内含水合物液膜的厚度测量问题,基于电-声联合探测方法原理设计了集成同轴圆盘-双环电极和超声晶片的内嵌凹面式电-声复合传感器,建立了数值仿真模型对传感器的结构和工作参数进行了优化,并分别对含有离散分布水合物颗粒和水合物沉积层液膜的厚度进行了仿真测量,讨论了电阻法和超声渡越时间法的适用性;研究结果表明:同轴圆盘-双环电极中的圆盘电极的半径、圆盘电极/内环电极的间距是影响电学测试空间灵敏度的主要结构参数,超声波频率对声学测试空间灵敏度产生显著影响,因此需要对凹面式电-声复合传感器的参数进行优化设计;电阻法和超声渡越时间法分别适用于测量水合物以离散颗粒形态分布和以沉积层形态分布的液膜,两类方法优势互补显著,拓宽了电-声复合传感器的适用范围。

Simulation study on measurement of hydrate-bearing liquid film thickness based on electrical-acoustic compound sensor

To measure the liquid film thickness containing hydrate in natural gas pipelines, an embedded concave electrical-acoustic compound sensor was designed based on the principle of electrical-acoustic joint detection method. A numerical simulation model was established to optimize the structure and working parameters of the sensor, and the liquid film thickness with discrete hydrate particles and hydrate deposition layers was measured by simulation. Finally the applicability of the resistance method and ultrasonic transit time method was discussed. The radius of the disk-shaped electrode and the distance between the disk-shaped electrode and the inner ring electrode are the major structural parameters that affect the spatial sensitivity of the electrical test. The ultrasonic frequency has a significant impact on the spatial sensitivity of the acoustic test. Therefore, it is necessary to optimize the parameters of the concave electrical-acoustic compound sensor. The resistance method and ultrasonic transit time method are suitable for measuring the liquid film with discrete particles and sedimentary layer, respectively. The advantages of the two methods are complementary to each other, thus the application range of the electrical-acoustic compound sensor is greatly widened.