1998 年 64 巻 627 号 p. 3597-3602
The trajectories of a single bubble in tap water and turbine oil in a horizontal spiral tube, in which a swirling flow occurs, is investigated numerically using the Lagragian method. Bubbles in the range of 0.5 to 3.0 mm diameter were used in the simulation. The results show that the bubbles converged at a certain radius and the radius increases with an increase of the bubble diameter and viscosity. The formula for critical convergent radius is obtained using dimensional analysis.