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多模态电学层析成像系统气液两相流持液率及流量对比分析研究
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Abstract:
为精准量化气液两相流核心参数(持液率、液相/气相流量)，解决不同流型、工况下参数计算精度不足的问题，结合4类持液率计算方法与4类流量计算模型，基于多模态电阻层析成像(ERT1/ERT2)与电容层析成像(ECT)系统，开展气多相流实验分析。通过数据热图、方法对比、时间序列分析、概率密度分布及质量评估雷达图等多维度分析框架，系统验证不同计算方法的适用性与单系统特性。结果表明：ERT1系统稳定性最优(变异系数23.3%)，Otsu阈值法在三系统中一致性最高(77.6% ± 19.8%)，其平均误差 ≤ 6%；ECT对气液界面响应敏感，适合流型识别(双组分分布验证厚液膜特征)，ERT1定量计算精度最优(误差 ± 2%)，多系统融合可互补传感盲区，将综合误差从±12.6%降至±5%。4类流量计算模型中，修正型模型精度最优(误差 ± 2%)，适配工业现场温压波动场景。该研究为气液两相流参数在线精准测量提供了理论方法与实验依据。
To accurately quantify key parameters of gas-liquid two-phase flow (liquid holdup, liquid/gas flow rates) and address insufficient calculation accuracy under different flow patterns and working conditions, four types of liquid holdup calculation methods and four types of flow rate calculation models are connected. Based on multimodal electrical resistance tomography (ERT1/ERT2) and electrical capacitance tomography (ECT) systems, a calibration experiment was conducted under horizontal flow conditions. Through a multidimensional analysis framework including data heatmaps, method comparison, time？series analysis, probability density distribution, Gaussian mixture modelling, and quality assessment radar charts, the applicability of different calculation methods and the characteristics of individual systems were systematically validated. The results show that the ERT1 system exhibits the best stability (coefficient of variation 23.3%), and the Otsu threshold method achieves the highest consistency across the three systems (77.6% ± 19.8%) with an average error ≤ 6%. The ECT system is sensitive to gas-liquid interfaces and is suitable for flow pattern identification (two？ component distribution verifies thick liquid film characteristics). ERT1 provides the best quantitative calculation accuracy (error ± 2%). Multi？system fusion can compensate for sensing blind spots, reducing the comprehensive error from ±12.6% to ±5%. Among the four types of flow rate calculation models, the modified model delivers the highest accuracy (error ± 2%) and is suitable for industrial scenarios with temperature and pressure fluctuations. This study provides theoretical methods and experimental evidence for accurate online measurement of gas-liquid two？phase flow parameters.
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