Understanding of Fluidic Physics during Bypass of a Taylor Bubble around a Transverse Insert in a Viscous Medium

Abstract

Fluidic physics during bypass of a Taylor bubble around a transverse insert is experimentally observed in a viscous liquid medium. Unified and fragmented bypasses are identified depending on the length scale of the insert. Sequential stages of these mechanisms are elaborated on from the kinematics of the bubble. Prediction of the bypass and pinch-off time scale validates the required diameter ratio between the insert and tube for a transition. Using photographic analysis, phenomena like airjet plunging, neck recovery, and shape transformation of daughter bubbles are discussed for the bypass and pinch-off systems. The 2D collapse of the gas stem at the initial stage and the volumetric pinch-off in the later stages have been conceptualized. The stability of the bubble train in pinch-off systems is evaluated, and coalescing/noncoalescing trains are identified by predicting the wake length. A pressure-jump model has been proposed to identify the reason for bubble-unified bypass and pinch-off.

Experimental Study on the Interfacial Evolution of Taylor Bubble at Inception of an Annulus

“…But in buoyancy driven flow of the bubble, further reduction of the gap between the annulus and the tube would hinder the bubble to enter into the gap due to the dominance of the surface forces over buoyancy ( Bo ∼ 4) . Recently, similar observations have been also reported by Rohilla and Das …”

“…9 Recently, similar observations have been also reported by Rohilla and Das. 40 3.2. Effect of Eccentricity on the Rise Velocity of Annular Bubble and Reacceleration Process.…”

Passage of a Taylor Bubble through a Stratified Liquid–Liquid Interface

“…They modeled the different density and viscosity fluids separated by a sharp interface with a low density bubble approaching the composite interface. The large volume of the bubble in a confinement acquires the shape of a slug/Taylor bubble − which has a spherical cap and cylindrical body with a thin annular film around it.…”