THERMAL SCIENCE

International Scientific Journal

NUMERICAL STUDY TO INVISTIGATE THE EFFECT OF INLET GAS VELOCITY AND REYNOLDS NUMBER ON BUBBLE FORMATION IN A VISCOUS LIQUID

ABSTRACT
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.
KEYWORDS
PAPER SUBMITTED: 2014-08-25
PAPER REVISED: 2015-01-18
PAPER ACCEPTED: 2015-01-24
PUBLISHED ONLINE: 2015-02-08
DOI REFERENCE: https://doi.org/10.2298/TSCI140825015I
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2015, VOLUME 19, ISSUE Issue 6, PAGES [2127 - 2138]
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