International Journal of Multiphase Flow, Vol.34, No.11, 1031-1047, 2008
Gas-liquid two phase flow measurement method based on combination instrument of turbine flowmeter and conductance sensor
In order to solve the flowrate measurement problem of gas-liquid two phase flow widely existing in gas wells of Daqing oil field in China, a new method has been developed, which is based on the combination instrument of turbine flowmeter and conductance sensor with petal type concentrating flow diverter. The turbine and conductance signals under 104 different flow conditions have been acquired through oil-gas-water three phase flow loop experimental facility. To determine the flow pattern in measurement channel, attractor morphologic characteristics are extracted from the conductance signals. For the total flowrate measurement, based on the turbine fluctuant signals of gas-liquid two phase flow, a statistical model with the average error of 7.9% is set up. With regard to the water cut measurement, the characteristics in time and frequency domains are extracted from the fluctuant conductance signals, and then employing the Support Vector Machine (SVM) soft measurement model used in high-dimension data fitting, the water cut prediction is realized with the average error of 0.038. The results show that the combination instrument of turbine flowmeter and conductance sensor with petal type concentrating flow diverter would be useful in measuring the total flowrate and water cut of gas-liquid two phase flow in gas production wells. (C) 2008 Elsevier Ltd. All rights reserved.
Keywords:Gas-liquid two phase flow;Turbine flowmeter;Conductance sensor;Flow pattern characteristics;Water cut;Soft measurement technique