Research On Measurement Method Of Gas-liquid Two-Phase Flow Based On Cylinder Electrode Array Capacitive Sensor

The gas-liquid two-phase flow is the most common flow systems among various multiphase flow systems in which the industrial production process.In recent years,with the progress of science and technology and the development of industrialization,higher efficiency is needed by industrial production.So the parameter detection technology of gas-liquid two-phase flow is becoming increasingly important in scientific research,industrial production and environmental protection.The gas-liquid two-phase flow parameter detection technology has been vigorously developed,with the wide application of mature detection technology,and the improvement and promotion of new theories and technologies,and the introduction of theories and methods in different fields.As one of the more mature methods of gas-liquid two-phase flow parameter detection,capacitance method has been widely used and studied.However,capacitive sensors still have some shortcomings,such as the difference of response to different flow patterns and the uneven sensitivity distribution,etc.In addition,the detection effect of two-phase flow parameters for large pipelines is not ideal.In this paper,a new type of capacitive sensor with coaxial cylinder electrode array is proposed.Based on the principle of electromagnetic field and finite element method,the coaxial cylindrical electrode array capacitive sensor was analyzed and studied.The paper use finite element simulation software and orthogonal experimental method to analyze the sensitive field characteristics of the capacitive sensor and its response characteristics to different flow patterns in detail.Firstly,the paper briefly introduces the research status of gas-liquid two-phase flow and the technology of two-phase flow parameter measurement,and the basic principle of capacitance sensor and the principle of voidage measurement in detail.At the same time,the finite element principle of electrostatic field is introduced,and the structure optimization index of capacitive sensor is analyzed.Secondly,according to the theoretical basis of the sensor optimization design,the structure of the capacitive sensor with coaxial cylindrical electrode array is designed.Using the finite element simulation software,the paper carries out the simulation calculation on the two-dimensional model of the sensor.Combined with the orthogonal experiment,the optimal structural parameters of a group of capacitive sensors were obtained from the perspective of capacitive sensor performance index.Finally,this paper have analyzed and studied field characteristics and response characteristics of each sub-detection field.The design of the capacitive sensor with coaxial cylindrical electrode array is verified according to the void fraction simulation experiment,which proves that the sensor can be used in the void fraction detection of gas-liquid two-phase flow where neither of the two phases is conductive.