Publicado 6 números por año
ISSN Imprimir: 2152-5102
ISSN En Línea: 2152-5110
Indexed in
NUMERICAL SIMULATION AND FUNDAMENTAL CHARACTERISTICS OF SURFACE FLOW GENERATED BY BUBBLY FLOWS
SINOPSIS
The motivation of this paper is to determine the characteristics of the surface flow induced by a bubble plume, which depends on the gas flow rate, bubble size, and internal two-phase flow structure of the bubbly flow. This paper is concerned with the numerical analysis of a surface flow generation process by buoyant bubbles in the two-dimensional and three-dimensional flow analysis based on the Eulerian-Lagrangian model. This is formulated with emphasis on the translational motion of bubbles. The technique of utilizing a surface flow generated by a bubbly flow could be employed as an effective way to control and collect the surface-floating substances in naval systems, lakes, seas, rivers, and oceans, as well as in various kinds of engineering processes involving a free surface. However, the detailed mechanism of the surface flow generation process has not previously been measured. The aim of this study is to clarify the applicability of a bubbling jet flow in order to control the transportation of surface-floating substances on a free surface. The numerical results presented in this paper reveal the characteristics of the fluid dynamics in the surface flow generation process. Furthermore, parametric dependency of the surface flow structure on the bubbling conditions is shown. The results presented in this paper clarify that the surface velocity profile that can be predicted by the Eulerian-Lagrangian model is in good agreement with the results of the experiments shown in our earlier paper. The surface flow is effectively generated in the case of a bubble plume compared to a liquid jet flow because a distortion point appears in the vicinity of the surface. The study also illustrates that the effective thickness of the surface flow is much less in the case of a free surface than in the case of a nonslip condition. The effective thickness of the surface flow increases when a liquid jet flow is provided instead of the bubble plume. The surface flow involves a wavy fluctuation under the free surface.
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Nguyen Viet-Bac, Do Quoc-Vu, Pham Van-Sang, An OpenFOAM solver for multiphase and turbulent flow, Physics of Fluids, 32, 4, 2020. Crossref