After combined vibration apparatus with experiment loop of two-phase flow
gas-liquid two-phase flow in inclined pipe was studied experimentally under fluctuant vibration. The flow patterns were recorded and pressure fluctuation signal was analyzed by multiscale entropy method. The results indicate that two new flow patterns of bead flow and fluctuant slug flow are created in inclined pipe under vibration condition. Multiscale entropy analyses were performed on pressure fluctuation signals of five typical flow patterns under 95 different flow conditions. Results show that entropy change rate of different flow patterns at low scale (first nine) is obviously different and entropy at high scale can reflect dynamic characteristics of different flow patterns.