针对大庆油田气井内广泛存在的气液两相流流量测量问题,提出了伞集流式涡轮流量计与电导传感器组合的气液两相流流量测量方法,并采集了104组不同流动工况下气液两相流的涡轮和电导波动信号.采用从电导波动信号中提取的吸引子形态特征量对伞集流后测量通道内的气液两相流流型进行辨识,取得了较好的流型分类效果.在总流量为0.1~2.5m^3/h、含水率为0.04~0.97范围内,基于气液两相流涡轮波动信号建立了总流量测量模型,预测总流量绝对平均相对误差为7.9%.从电导传感器测取的波动信号提取了与相含率有关的时频域特征量,通过支持向量机软测量模型实现了含水率预测,预测含水率绝对平均误差为0.038.研究结果表明,采用伞集流涡轮流量计与电导传感器组合可以较好地测量气液两相流流量和相含率.
In order to solve the flow measurement problem of gas-liquid two-phase flow that widely exists in gas wells of Daqing oil field, a method was proposed based on petal type concentrating combination instrument of turbine flowmeter and conductance sensors. The turbine and conductance fluctuant signals under 104 groups of flow conditions were acquired. The attractor morphologic characteristics extracted from conductance fluctuant signals were used to recognize the gas-liquid flow patterns in concentrating channel, and desirable results were obtained. At the total flow range of 0.1-2.5 m^3/h and the water volume fraction range of 0.04-0.97, total flow measurement model was established based on turbine fluctuant signals, whose prediction absolute average percent deviation was 7.9%. Characteristics of time and frequency domain related to phase volume fraction were also extracted from conductance fluctuant signals, and then the water volume fraction prediction was realized by support vector regression (SVM) soft measurement model with its prediction absolute average deviation being 0.038. The results show that the petal type concentrating combination instrument of turbine flowmeter and conductance sensors can be used to measure flow and phase volume fractions.