油气水三相段塞流与滚动波流型的转变

Transition from slug flow to roll wave flow in oil-gas-water three-phase horizontal pipe

Compared with gas-liquid two-phase flow,oil-gas-water three-phase flow is much more complex.There is immiscible oil-water,whose interaction and dispersion greatly affects the flow characteristics.The slug flow pattern of oil-gas-water three-phase and its flow pattern transition were studied in a 95 m long,51 mm i.d.horizontal pipe.The oil-gas-water three-phase slug flow pattern could be classified into five sub-flow patterns.The slug flow was W/O or O/W one during its transition to roll wave,which was three-layer flow pattern without mixed-phase on the interface.An even larger superficial gas velocity was needed for the transition boundary of slug flow and roll wave flow when the superficial liquid velocity is large.Besides,the region of roll wave flow pattern became smaller.The above-mentioned transition only happened when the water cut of liquid was between 30% and 70%.At the same superficial liquid velocity,there appeared a minimum superficial gas velocity corresponding to the transition of flow pattern when the water cut of liquid was between 40% and 50%.