1994 年 60 巻 570 号 p. 552-559
Experimental data are presented on the liquid lump velocities in vertical upward gas-liquid two-phase flow. The liquids used in this experiment are water and glycerol solutions, and the kinematic viscosity of these liquids ranges from 1.0×10-6 to 15.5×10-6 m2/s. Flow regimes concerned herein cover plug flow, huge wave flow and annular flow. Velocities of liquid lumps, such as liquid slugs, huge waves, disturbance waves or ephemeral large waves, are determined using two sets of signals of time-varying cross-sectional mean liquid holdups which are electrically detected at two axially separated locations in the test tube. It is first described, from the observations of liquid holdup signals, that the liquid viscosity affects the formation of liquid lumps or the appearance frequency of the same kind of liquid lump under the same gas and liquid flow rates. Next, the mean values of liquid lump velocity and their standard deviations are discussed with attention paid to the effect of liquid viscosity.