Abstract Coalescence and breakup in a swarm of bubbles were directly observed by using the high speed cinematography. It was designed so that three dimensional motion of bubbles could be continually followed. Influence of operating conditions and liquid properties on the frequencies of bubble passing, coalescence and breakup was examined. It was seen that there was the critical distance at which the leading bubble began to exert an noticeable influence on, the following one. The distance was about 3- to 4-fold diameter of the leading bubble. Coalescence was found to take place when more than about a half of the projected area of the following bubble was overlapped with that of the leading bubble at the critical distance. On the contrary, breakup occurred in the case of the overlapping less than about a half of the projected area of the following bubble. The increment of the following bubble velocity induced by the leading one was empirically correlated with the bubble distance and the angle between the straight line joining the centers of bubbles and the vertical axis. The Reynolds numbers had no appreciable effect on the velocity increment within the range examined.
[1]
Shiro Maeda,et al.
On the Shape and Velocity of Single Air Bubbles Rising in Various Liquids
,
1961
.
[2]
S. Narayanan,et al.
Coalescence of two bubbles rising in line at low reynolds numbers
,
1974
.
[3]
J. M. Burgess,et al.
The measurement of bubble parameters in two-phase dispersions—II: The structure of sieve tray froths
,
1975
.
[4]
H. Karam,et al.
Deformation and Breakup of Liquid Droplets in a Simple Shear Field
,
1968
.
[5]
E. Rushton,et al.
The slow unsteady settling of two fluid spheres along their line of centres
,
1973
.
[6]
J. Hinze.
Fundamentals of the hydrodynamic mechanism of splitting in dispersion processes
,
1955
.
[7]
J. Bridgwater,et al.
Bubble coalescence in viscous liquids
,
1971
.
[8]
F. A. Morrison.
Breakup of a bubble chain
,
1973
.
[9]
N. Nevers,et al.
Bubble coalescence in viscous fluids
,
1971
.