THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Weiyu Liu

,

Zhenhua Jiang

,

Baoyu Yang

,

Zhe Yan

,

Zhenhai Pan

online first only

Numerical study on bubble merger in a heated symmetric microfluidic T-junction

ABSTRACT
In this work, the bubble merger process in a heated symmetric microfluidic T-junction is numerically studied with the variations of heat flux and seed bubble volume. Detailed bubble behaviors and phase change heat transfer characteristics are revealed. Results show that the bubble experiences slipping and colliding merger regimes at small and large seed bubble volumes, respectively. The bubble grows faster at large heat flux and seed bubble volume. Obvious peak in evaporation rate during the bubble merger can be seen. The bubble behaviors significantly affect the phase change heat transfer. The asymmetry of bubble behaviors under slipping merger regime leads to the heat transfer difference between two main channel walls. Besides, the squeezing effect during bubble merger could promote the heat transfer. Generally, the heat transfer enhancement becomes stronger as the heat flux and seed bubble volume are increased. The present study's findings could improve the understanding of bubble behaviors and transport details in microfluidic T-junction structures.
KEYWORDS
Microfluidic T-junction, bubble merger, phase change, heat transfer, VOF Method
PAPER SUBMITTED: 2024-10-04
PAPER REVISED: 2024-12-12
PAPER ACCEPTED: 2024-12-12
PUBLISHED ONLINE: 2025-02-16
DOI REFERENCE: https://doi.org/10.2298/TSCI241004014L
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Numerical study on bubble merger in a heated symmetric microfluidic T-junction