Local bubble slip velocity in a downward laminar tube flow
L.S. Timkin, R.S. Gorelik
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Keywords: ламинарное опускное течение, электродиффузионный метод, ЛДА, локальная скорость скольжения пузырьков, laminar downward flow, electrodiffusional technique, LDA, local bubble slip velocity
Abstract
The paper presents a study of the slip velocity for almost spherical bubbles in a downward laminar tube flow. The local slip velocity is defined as a difference between the mean liquid velocity (measured with electrodiffusional method) and the mean bubble velocity (measured with a modified LDA tool with a small size of measurement volume). The law for slip velocity for downward flow is significantly different from a similar law for upward flow. This reveals that the bubble flow motion is rather random than structured in the downward flow.
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