中文摘要：

将符号时间序列分析方法应用到两相流测量波动信号分析，并讨论了关键参数对符号统计量影响问题。在此基础上，利用垂直上升管中采集到的80组气液两相流差压动态波动信号，提取了时间不可逆转性Tfb及xfb^2统计量。当气相表观速度小于0．02m·s^-1时，随着气相表观速度增加，泡状流随机可变的运动特征逐渐加剧，其动力学特性变得相对复杂；当气相表观速度大于0．02m·s^-1时，在流型从泡状流向段塞流转变过程中，随着气相表观速度增大，流型演化的动力学特性逐渐变得相对简单；在流型从段塞流向混状流转变过程中，随着气相表观速度增加，混状流的动力学特性逐渐变得愈加复杂。研究结果表明，时间不可逆转性R及梳统计量两个符号是表征气液两相流流型的敏感特征量，考察这两个统计量随两相流流动参数变化规律有助于更好地理解两相流流型动力学特性。

英文摘要：

The symbolic sequence statistical analysis method was applied to analyze two-phase flow measurement fluctuating signals and the key parameters affecting the symbolic statistical quantities were discussed. Based on the above study, eighty groups of differential pressure fluctuating signals of gas/liquid two-phase flow in vertical upward pipes were gathered and the statistical quantities of time irreversebility Tfb and chi-square statistics xfb^2 were extracted. When the gas superficial velocity was less than 0.02 m·s^-1 , the randomly variable motion features of bubble flow became stronger and the dynamic characteristics became relatively more complex with increasing gas superficial velocity. When gas superficial velocity exceeded 0.02m·s^-1 , with increasing gas superficial velocity the flow pattern changed from bubble flow to slug flow and the dynamic characteristics became relatively simple, while with further increasing gas superficial velocity the flow pattern changed from slug flow to churn flow and the dynamic characteristics became more complex. This study showed that time irreversibility Tfb and chi-square statistics xfb^2 were sensitive statistical quantities characterizing gas/liquid two-phase flow pattern and the dynamic characteristics of gas/liquid two-phase flow pattern could be better understood by observing the change of these two statistical quantities with changing two-phase flow parameters.