ABSTRACT
This chapter focuses on presenting a numerical method for two-phase flows in microscale systems using the level-set method of S. Osher and J. A. Sethian. The emerged bubble is further deformed by the hydrodynamic force downstream of the flow field. Generally, the fluid flows faster in the small channel. A lower pressure is developed in the small channel, sucking the bubble into the small channel. In the middle of the small channel, the fluid particles flow faster than those near the wall. Because the cusp is driven by a larger velocity at the middle of the channel, it becomes longer and sharper. Once in the small channel, the deformed bubble is squeezed by the main stream through the small channel. At the exit of the small channel, the flow expands because there is a sudden increase in cross-sectional area.
