A general model for the transition to gas-liquid dispersed bubble flow
is proposed in this paper, based on an assumption that dispersed bubb
le flow cannot exist unless the turbulent kinetic energy of the liquid
phase is greater than the surface free energy of dispersed spherical
bubbles. This model is capable of predicting the transition boundary t
o dispersed bubble flow in various closed channels over the whole rang
e of inclination angles. It also yields a good prediction for the slug
liquid holdup in gas-liquid slug how in conjunction with the Barnea-B
rauner hypothesis (1985, Int. J. Multiphase Flow 11, 43-49). (C) 1997
Elsevier Science Ltd.