A simple 2D model of the bubble formation in a plasma wakefield accelerator is developed and investigated. It shown that case flat driver may consist two parts correspond to different types flow: laminar flow where electron streams do not cross two-stream (turbulent) flow. The turns out be robust symmetry breaking. Building-of we demonstrate non-relativistic electrons transverse wake field abse...

A one-pot single-step novel process has been developed to form microbubbles up to 250 μm in diameter using a pressurized rotating device. The microbubble diameter is shown to be a function of rotational speed and working pressure of the processing system, and a modified Rayleigh-Plesset equation has been derived to explain the bubble-forming mechanism. A parametric plot is constructed to identi...

The evolution of carbon dioxide bubbles dissolving in water is experimentally examined using long microchannels. We study the coupling between bubble hydrodynamics and dissolution in confined geometries. The gas impregnation process in liquid produces significant flow rearrangements. Depending on the initial volumetric liquid fraction, three operating regimes are identified, namely saturating, ...

Abstract We performed a characterization of the bubbly and slug flow regimes in minichannels in conditions relevant to microgravity. Two-phase flows were generated on ground by means of a T-junction device (1 mm i.d.), whose operation is independent to changes in gravity level [1]. Air and water were injected at several superficial velocities ranging from 0 up to 2 m/s. The generation and detac...

Sonoluminescence is the intriguing phenomenon of strong light flashes from tiny bubbles in a liquid [1]. These bubbles are driven by an ultrasonic wave and need to be filled with noble gas atoms. The spectrum of the emitted light corresponds to very high temperatures [2] and hints the presence of an hot opaque plasma core [3]. Although sonoluminescence has been studied extensively, the origin o...

We report how a nominally symmetric microfluidic junction can be used to sort all bubbles of an incoming train exclusively into one of its arms. The existence of this "filter" regime is unexpected, given that the junction is symmetric. We analyze this behavior by quantifying how bubbles modulate the hydrodynamic resistance in microchannels and show how speeding up a bubble train whilst preservi...

Digital Image Analysis (DIA) has been employed to characterize the time evolution of a bubble injected from a single orifice into a pseudo 2-dimansional gas-solid fluidized bed. The injected bubble diameter increased with the square root of time before detachment. During bubble free flight in the bed, its diameter remains approximately constant. The center of mass of the bubble increases with t...