Abstract: The Hilbert-Huang transform(HHT) was used to analyze the differential fluctuation signal of gas-liquid two-phase flow in a horizontal pipeline. By using the empirical mode decomposition(EMD) method, the signal was decomposed into a finite and small number of intrinsic mode function(IMF), and then the Hilbert transform was applied to each of these intrinsic mode functions to get the energy-frequency-time distribution, designated as the Hilbert spectrum. The energy characteristics of different intrinsic mode functions was extracted to characterize the differential pressure fluctuation signal. Based on the above analysis, a comparison of the results for different diameters of pipeline was presented and the relationship between the energy distribution of signals of different frequency bands and flow pattern conversion was analysed. Meanwhile, the differences between the wavelet method and HHT method were also discussed. The experimental results show that the HHT is an extremely powerful tool for the analysis of nonlinear and non-stationary signals，and the extracted energy characteristics can reflect the flow state of gas-liquid two-phase flow and flow pattern conversion.This method could be useful for the signal analysis in gas-liquid two-phase flow in a horizontal pipeline.

摘要： 将Hilbert-Huang（HHT）变换应用于中小管径水平管气液两相流差压波动信号的分析.利用经验模态分解（EMD）方法把信号分解成多个内模函数(IMF)，再对各内模函数进行Hilbert变换，得到信号的Hilbert谱，并提取各内模函数的信号能量特征.在此基础上比较了不同管径下信号分析的结果，分析了不同频段的能量分布与流型变迁的关系，并讨论了小波变换和HHT两种信号处理方法各自的特点.实验结果表明，HHT可以用于非线性非平稳信号的分析，提取的能量特征值反映了水平管气液两相流的流动状态和流型的变迁，该方法为水平管气液两相流差压波动信号的研究提供了借鉴.