Modeling of the Free-Surface Vortex-Driven Bubble Entrainment into Water

Modeling bubble-vortex interactions Modeling and simulation of multiple bubble entrainment and interactions with two dimensional vortical flows

1 Modeling bubble-vortex interactions Simulations of bubble entrainment and interactions with two dimensional vorti-cal flows are preformed using a Discrete Element Model (DEM). In this Eulerian-Lagrangian approach, solution to the carrier phase is obtained using direct numerical simulation whereas motion of subgrid bubbles is modeled using Lagrangian tracking. The volumetric displacement of th...

Modeling Turbulent Entrainment of Air at a Free Surface

Overview In free-surface flows the turbulence in the liquid may be sufficient to disturb the surface to the point of entraining air into the flow. This process is important, for example, in water treatment where air is needed to sustain microorganisms for water purification and in rivers and streams for sustaining a healthy fish population. Air entrainment is typically engineered into spillways...

Contributions to modeling of bubble entrainment for ship hydrodynamics applications

Air entrainment through free-surface cusps.

In many industrial processes, such as pouring a liquid or coating a rotating cylinder, air bubbles are entrapped inside the liquid. We propose that this is due to air being drawn into the narrow channel of a cusp singularity that generically forms on free surfaces. Since the width of the cusp is exponentially small in the driving strength, even the minute viscosity of air is enough to destroy t...

Turbulent Vortex Ring I Free Surface Interaction

Graduate Aeronautical Laboratories, Californ ia Institute ol Technology, Pasadena. CA 91125 The interaction of turbulent vortex rings that approach a clean water surface under various angles is experimentally investigated. The temporal evolution of the vortex rings with an initial Reynolds number of Re0 = 7500 is characterized by the Laminar/ turbulent transition and asymptotic relaminarization...