NUMERICAL-ANALYSIS OF DETAILED FLOW STRUCTURES OF A BUBBLE PLUME

Detailed flow structure of bubbly flours observed in a bubble plume is investigated numerically using the Euler-Lagrange model where the bub bly flow is treated as a continuum and each bubble is tracked in the f low. The governing equations are formulated with emphasis on the trans lational motion of the bubble in non-uniform unsteady liquid flow. Imp rovement of the present numerical method is confirmed by comparison wi th the Eulerian method, and the numerical results are validated by the comparison with the two kinds of experimental results, i.e., global f low pattern visualized by direct-lighting method, and local bubble mot ion measured by particle imaging velocimetry. In this paper, two-dimen sional bubble plume which is confined by two parallel plates is analyz ed and the parametric dependency, such as influence of the bubble size distribution and void fraction, on the whole two-phase behavior is cl arified and experimental validation is conducted.