关键词: 电磁流量计, 电极尺寸, 电极位置, 干标定, 模型

Abstract: In the existing dry calibration models of electromagnetic flowmeters, size and position of electrodes are considered as two idealized characteristics, i.e., the electrodes are mounted on two symmetric points in the middle of the measuring pipe, their link line is perpendicular to magnetic field, and their sizes are infinitely small. Obviously, these idealized models are different from real flowmeters, and not enough perfect to be used in dry calibration technique. The defective models limit the technique’s accuracy and increase its requirement for product consistency. For solving this problem, a new dry calibration model including size and position characteristics of real flowmeter electrodes is acquired by the method called “separation of variables”, which is more close to real flowmeters comparing to the existing dry calibration models. This is helpful to increasing the accuracy of dry calibration technique, and reducing its requirement for product consistency. The accuracy of the new model is also certified by comparing with the existing dry calibration models and numerical simulation.

Key words: Dry calibration, Electromagnetic flowmeter, Model, Position of electrodes, Size of electrodes