Air cushioning and bubble entrapment in three-dimensional droplet impacts

Air entrapment and air bubble dispersion at two-dimensional plunging water jets

Air—water bubbly flows are encountered in numerous engineering applications. One type of air—water shear flow, the developing flow region of a plunging jet, is discussed in the light of new experimental evidence. Distributions of air concentration and mean air—water velocity, and bubble chord length distributions are presented for inflow velocities ranging from 2 to 8 m/s. The results indicate ...

Air entrapment and splashing treshold in drop impacts .

We investigate here how the surrounding gas influence the dynamics of drop impacts on a thin liquid film. We describe in details the entrapment of the gas bubble using numerical simulations with high enough mesh resolution. The bubble entrapment comes from viscous effect in the thin gas layer that need to be evacuated down the drop, creating a high pressure field that deforms the drop interface...

Air-cushioning in impact problems

Air cushioning with a lubrication/inviscid balance

The air cushioning effect in the gap between an almost inviscid body of water and a nearby solid wall (or another body of water) is studied theoretically and is found to depend on predominantly lubricating forces in the air, in certain applications. The situation in which the density and viscosity in air are taken as small compared with those in water is investigated. In this situation potentia...

Effect of Bubble/Droplet Morphology and Slippage on Attachment Induction Time in Deoiling Flotation Process

A modified model has been analytically developed to describe the induction time of an elliptic air bubble in contact with an elliptic hydrophobic oil droplet. The role of hydrophobicity was revealed in the slippage of liquid over the surfaces of bubble and droplet. In this condition, the analytical relationships for pressure distribution and consequently hydrodynamic resistance force through th...