Dynamic Characteristics of Bubble Collapse Near the Liquid-Liquid Interface

Yin, Zhonglong; Huang, Zhuoli; Tu, Chengxu; Gao, Xiaoyan; Bao, Fubing

doi:10.3390/w12102794

Cited by 11 publications

(3 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dependence of the bubble dynamics on an anisotropy parameter (Supponen et al 2016) was also discussed. A similar bubble jet behaviour was also reported in the work of Yin et al (2020). In the present work, the electric discharge method (Fong et al 2009;Cui et al 2018) is used to generate centimetre-scale cavitation bubbles, which allows us to achieve a higher spatio-temporal resolution of bubble dynamics and interface evolution than in earlier works.…”

Section: Introductionsupporting

confidence: 76%

Interaction of cavitation bubbles with the interface of two immiscible fluids on multiple time scales

et al. 2021

View full text Add to dashboard Cite

We experimentally, numerically and theoretically investigate the nonlinear interaction between a cavitation bubble and the interface of two immiscible fluids (oil and water) on multiple time scales. The underwater electric discharge method is utilized to generate a cavitation bubble near or at the interface. Both the bubble dynamics on a short time scale and the interface evolution on a much longer time scale are recorded via high-speed photography. Two mechanisms are found to contribute to the fluid mixing in our system. First, when a bubble is initiated in the oil phase or at the interface, an inertia-dominated high-speed liquid jet generated from the collapsing bubble penetrates the water–oil interface, and consequently transports fine oil droplets into the water. The critical standoff parameter for jet penetration is found to be highly dependent on the density ratio of the two fluids. Furthermore, the pinch-off of an interface jet produced long after the bubble dynamics stage is reckoned as the second mechanism, carrying water droplets into the oil bulk. The dependence of the bubble jetting behaviours and interface jet dynamics on the governing parameters is systematically studied via experiments and boundary integral simulations. Particularly, we quantitatively demonstrate the respective roles of surface tension and viscosity in interface jet dynamics. As for a bubble initiated at the interface, an extended Rayleigh–Plesset model is proposed that well predicts the asymmetric dynamics of the bubble, which accounts for a faster contraction of the bubble top and a downward liquid jet.

show abstract

Section: Introductionsupporting

confidence: 76%

Interaction of cavitation bubbles with the interface of two immiscible fluids on multiple time scales

et al. 2021

View full text Add to dashboard Cite

show abstract

“…micrometer droplets of one liquid in another) produced by ultrasonic cavitation. Despite the complexity and multitude mechanisms implicated in this process [19,20], it is generally accepted that the emulsion is mainly produced by bubble cavitation. Considering that spark ignition in liquid also induces bubble formation with expansionimplosion dynamics [21,22], it may be concluded that under certain conditions, discharges near the interface of two immiscible liquids may lead to emulsion formation.…”

Section: Introductionmentioning

confidence: 99%

Spark discharges at the interface of water and heptane: emulsification and effect on discharge probability

Dorval,

Stafford,

Hamdan

2023

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Spark discharges in liquid have shown great potential for use in numerous applications, such as pollutant degradation, precision micromachining, and nanomaterials production. Herein, spark discharges are initiated at the interface of two immiscible liquids, heptane and water. This leads to the formation of an emulsion via mechanisms akin to bubble dynamics and instabilities at the gas–liquid. At high discharge number, an additional mechanism contributes to emulsion formation, resulting in an increase in the number of smaller heptane droplets in water. Analyses of the current–voltage characteristics show that high probability of discharge occurrence is obtained when the electrodes are aligned with the interface. This result is correlated with the low erosion rate of the electrodes. In the case of discharges at the interface, we observed that beyond a certain number of discharges, the breakdown voltage drops; far from the interface, it increases with the discharge number. Based on 2D simulation with a Monte Carlo approach to consider various droplet distribution in water, the electric field distribution is determined. The results support the fact that the decrease in breakdown voltage may be attributed to the intensification of the E-field in water close the heptane droplet. Therefore, spark discharges generated at the interface of a heptane/water system produce an emulsion of heptane in water, which facilitates the occurrence of subsequent discharges by intensifying the electric field and reducing the breakdown voltage.

show abstract

“…The unsteady nature of cavitating flows (including the phenomena relevant to the cavitation cloud break-off at the macro-scale as well as bubble collapse at the micro-scale) generates pressure waves that travel throughout the domain [22,23]. These propagating waves will interact with the domain boundaries in different ways (varying from 100% reflection to 100% transmission) depending on the experimental set up.…”

Section: Introductionmentioning

confidence: 99%

Cavitation Bubble Cloud Break-Off Mechanisms at Micro-Channels

McGinn

Pearce

Hardalupas

et al. 2021

Fluids

View full text Add to dashboard Cite

This paper provides new physical insight into the coupling between flow dynamics and cavitation bubble cloud behaviour at conditions relevant to both cavitation inception and the more complex phenomenon of flow “choking” using a multiphase compressible framework. Understanding the cavitation bubble cloud process and the parameters that determine its break-off frequency is important for control of phenomena such as structure vibration and erosion. Initially, the role of the pressure waves in the flow development is investigated. We highlight the differences between “physical” and “artificial” numerical waves by comparing cases with different boundary and differencing schemes. We analyse in detail the prediction of the coupling of flow and cavitation dynamics in a micro-channel 20 m high containing Diesel at pressure differences 7 MPa and 8.5 MPa, corresponding to cavitation inception and "choking" conditions respectively. The results have a very good agreement with experimental data and demonstrate that pressure wave dynamics, rather than the “re-entrant jet dynamics” suggested by previous studies, determine the characteristics of the bubble cloud dynamics under “choking” conditions.

show abstract

Dynamic Characteristics of Bubble Collapse Near the Liquid-Liquid Interface

Cited by 11 publications

References 23 publications

Interaction of cavitation bubbles with the interface of two immiscible fluids on multiple time scales

Interaction of cavitation bubbles with the interface of two immiscible fluids on multiple time scales

Spark discharges at the interface of water and heptane: emulsification and effect on discharge probability

Cavitation Bubble Cloud Break-Off Mechanisms at Micro-Channels

Contact Info

Product

Resources

About