Terminal velocity of single bubbles in surface tension force dominant regime

Dynamics of an initially spherical bubble rising in quiescent liquid

“…One of our objectives is to standardize the initial conditions, a luxury not easily available to experimenters! A curious phenomenon, the path instability, has been the subject of a host of experimental [22][23][24][25] , numerical 26,27 and analytical 28,29 studies. This is the name given to the tendency of the bubble, under certain conditions, to adopt a spiral or zigzagging path rather than a straight one.…”

“…We will demonstrate that path and shape symmetry are intimately connected, but only the former has been measured experimentally. It is not easy to measure the evolving bubble shape 24 and flow field accurately in this highly 3D regime. Most of the workers embarking on this study find it satisfactory to investigate the effect of initial bubble diameter on the rising dynamics, and no experimental investigations are available to our knowledge which study the effects of just the surface tension or viscosity of water on the bubble rise.…”

Multiphase turbulence in bubbly flows: RANS simulations

“…The agreement is better for K4, which does not show the water velocity peak 1052 near the wall (Figure 12g Lastly, different drag models were also evaluated. Introducing the effect of bubble aspect 1159 ratio in the drag correlation, as in the model of Tomiyama et al (2002a), allowed the more 1160 accurate calculation of velocity profiles near the wall. In this work, the aspect ratio was 1161 evaluated through the correlation of Welleck et al (1966).…”

A moving mesh finite volume interface tracking method for surface tension dominated interfacial fluid flow

“…We consider bubbles in the range of equivalent radius r b = (0.7-1.1) mm corresponding to the flow regime where surface tension forces have dominant influence as described by Tomiyama [50]. Smaller bubbles (r b < 0.91) have a stable rectilinear path while larger bubbles have unstable zig-zag and/or helicoidal path [51,52].…”