Abstract
Time-evolutions of bubbling in viscous liquid are characterized by two stages, i.e., the bubble formation stage and the bubble coalescence stage. We have focused on the former stage of bubbling and investigated numerically bubble formation in viscous liquid decompressed with a constant rate. To describe bubble formation, some authors used the growth model proposed by Toramaru [1995]. In this model, all bubbles are assumed to be equal in size neglecting the bubble size distribution. To overcome this difficulty, we have developed more realistic model of bubble growth, taking into account bubble size distribution and compressibility of surrounding liquid. In a low viscosity case, the size distribution of bubbles shows an unimodal size distribution with a narrow dispersion. On the other hand, in a high viscosity case, it is observed that size distributions of bubbles gradually change from a power law to an unimodal distribution as bubbles grow more. These characteristic time-evolutions of size distribution of bubbles are made clear by our study and would be useful in evaluating material quantities such as the diffusivity, the viscosity, and the surface tension of liquid from experimental results.
