パターン認識法による気液二相流のボイド率信号解析と流動様式の判定

抄録

A statistical pattern recognition method was applied to the analysis of the signals of cross-sectional mean void fraction for discriminating gas-liquid two-phase flow regimes. The anaysis and discrimination were carried out based on six key flow patterns: bubble, cap-bubble, plug, froth (F_I and F_II), and annular flow. For each flow condition 100 void signals with a recording dimension of 1 second were used and transferred to discrete data, the sampling frequency of which was selected at 100 Hz by comparison between correct recognition rates obtained from different frequencies. The magnitude of the time-averaged void fraction was partly employed supplementary to the pattern recognition method. The boundaries between the six flow regimes were determined corresponding to a correct recognition rate of 80% and drawn on a superficial gas-liquid velocities diagram. These flow boundaries were also compared with those available in the literature.