Pii: S0301-9322(98)00066-4
نویسندگان
چکیده
The motion of elongated (Taylor) bubbles in air±water vertical ̄ow is studied by processing consecutive series of digitized video images. The shape of the elongated bubbles, as well as the velocities of the liquid±gas interfaces, are measured for various ̄ow conditions. The bubble velocity variation caused by air expansion under the in ̄uence of hydrostatic pressure gradient is measured and compared with model predictions. An oscillatory motion of the bubble bottom is observed. The frequency and the amplitude of these oscillations are studied as a function of bubble length and water ̄ow rate. This information is essential for accurate modeling of developing gas±liquid slug ̄ow. # 1999 Elsevier Science Ltd. All rights reserved.
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