The Transient Dynamics of a Small Bubble Rising in a Low Morton Number Regime

✍ Scribed by M. Ohta; M. Tsuji; Y. Yoshida; M. Sussman

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 660 KB
• Volume: 31
• Category: Article
• ISSN: 0930-7516
• DOI: 10.1002/ceat.200700507

✦ Synopsis

Abstract

The effect of initial bubble conditions on the transient dynamics of a small bubble (d = 1.5 mm) rising in water is computationally considered by a fully three‐dimensional direct numerical simulation. The numerical algorithm is based on the coupled level set/volume‐of‐fluid (CLSVOF) method for representing and updating the air‐water interface and the sharp interface approach is used to treat the air‐water interfacial boundary conditions. The transient bubble dynamics are investigated using bubbles with five different kinds of shapes as initial bubble conditions. It is shown computationally that the states of bubble shape, bubble trajectory, and terminal velocities greatly depend on initial conditions. As a consequence, the computational results have led us to conclusions in support of the experimental findings by Wu and Gharib [1] and Tomiyama et al. [2]. That is, the dynamic behavior of a rising bubble in a surface tension force dominant system is effected by the initial conditions.