TY - JOUR
TI - Numerical study to invistigate the effect of inlet gas velocity and Reynolds number on bubble formation in a viscous liquid
AU - Islam Md Tariqul
AU - Ganesan P
AU - Sahu J N
AU - Hamad F A
JN - Thermal Science
PY - 2015
VL - 19
IS - 6
SP - 2127
EP - 2138
PT - Article
AB - Bubble formation dynamics has great value in mineral recovery and the oil  industry. In this paper, a single bubble formation process through an orifice  in a rectangle domain is modelled to study the bubble formation  characteristics using the volume of fluid (VOF) with the continuum surface  force (CSF) method. The effect of gas inlet velocities, Ug ~ 0.1 - 0.3 m/s on  bubble formation stages (i.e., expansion, elongation and pinch off), bubble  contact angle, dynamics and static pressure, bubble departure diameter etc.  was investigated through an orifice diameter of 1 mm. The method was also  used to study the effect of Reynolds number, Reμ ~ 1.32 - 120 on bubble  formation when all other parameters were kept constant. It is found that a  high inlet gas velocity accelerated the reducing of the bubble contact angle  from an obtuse angle to an acute angle and the faster development of  hemispherical shape of the bubble. It is also found that an increasing of  Reynolds number caused speeding up of the bubble pinch-off and formed a  smaller bubble neck height due to stronger vortex ring around the bubble  neck.