K. Jagannath and Akhilesh Kotian and S. S. Sharma and Achutha Kini U. and P. R. Prabhu Investigation of Bubble Growth during Nucleate Boiling Using CFD
1059 - 1063
2015
9
6
International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering http://waset.org/publications/10001785
http://waset.org/publications/102
World Academy of Science, Engineering and Technology
Boiling process is characterized by the rapid
formation of vapour bubbles at the solid–liquid interface (nucleate
boiling) with preexisting vapour or gas pockets. Computational fluid
dynamics (CFD) is an important tool to study bubble dynamics. In
the present study, CFD simulation has been carried out to determine
the bubble detachment diameter and its terminal velocity. Volume of
fluid method is used to model the bubble and the surrounding by
solving single set of momentum equations and tracking the volume
fraction of each of the fluids throughout the domain. In the
simulation, bubble is generated by allowing watervapour to enter a
cylinder filled with liquid water through an inlet at the bottom. After
the bubble is fully formed, the bubble detaches from the surface and
rises up during which the bubble accelerates due to the net balance
between buoyancy force and viscous drag. Finally when these forces
exactly balance each other, it attains a constant terminal velocity. The
bubble detachment diameter and the terminal velocity of the bubble
are captured by the monitor function provided in FLUENT. The
detachment diameter and the terminal velocity obtained are compared
with the established results based on the shape of the bubble. A good
agreement is obtained between the results obtained from simulation
and the equations in comparison with the established results.
International Science Index 102, 2015