基于空隙率波特性的垂直气液两相流流型判别研究

Study of flow pattern discrimination in vertical gas-liquid two-phase flow based on the characteristics of void fraction waves

通过实验得到了垂直管内气液两相流动各种流型的空隙率波,对空隙率波进行信号处理,得到了泡状流、弹帽泡状流、段塞流、沫状流等各种基本流型的空隙率概率密度分布规律和频谱。结果表明,不同流型的空隙率波、概率密度函数(PDF)曲线和频谱曲线具有不同的特征,截面平均含气率越高,空隙率波的频率越趋于单一。因此在不可视的条件下可以根据空隙率波特性,利用这些曲线特别是PDF曲线特性判别流型。

Void fraction waves of various flow patterns in vertical gas-liquid two-phase flow were obtained from experiments. The probability distribution function (PDF) and spectral distribution of various basic flow patterns such as bubble flow, cap bubble flow, slug flow and churn flow were gained by means of signal processing. The results indicate that the characteristics of void fraction waves, PDF and spectral distribution of different flow patterns are different. With the increase of void fraction, the frequencies of void fraction waves come to single. Therefore, on condition of invisualization, different flow patterns can be distinguished by means of curve characteristics above, especially the PDF distribution curves.