An Electrical and Ultrasonic Doppler System for Industrial Multiphase Flow Measurement

Abstract

Accurate measurement of flow parameters of multiphase flow has great significance for safe, economic, and efficient operation of the industrial production process. To simultaneously measure the water holdup and velocity, a combined electrical and ultrasonic Doppler measurement system based on a compact peripheral component interconnect (CPCI) bus is designed. The combined sensor consists of a six-ring conductance sensor, two pairs of capacitance plate sensors, and an ultrasonic Doppler sensor. The measurement system is cored with a field-programmable gate array (FPGA) and consists of a series of functional modules. Through flexible programming and interboard communication, the system can meet different measurement requirements. To meet industrial data transmission standards and increase system extensibility, the demodulated data are transmitted to a host computer through the CPCI bus for further data analysis. Dynamic experiments demonstrated that the multimodal system has stable and preferable performance in water holdup and velocity measurement under all flow patterns. The conductance and capacitance sensor could realize the water holdup measurement with the root-mean-square error (RMSE) of 3.02% and the overall superficial velocity estimation through cross correlation with the RMSE of 0.09 m/s. Besides, the pulse ultrasonic Doppler transducer could measure the overall superficial velocity through the area integration of the velocity profile with the RMSE of 0.08 m/s.