Axisymmetric bubble collapse in a quiescent liquid pool. II. Experimental study

Bolaños-Jiménez, R.; Sevilla, A.; Martı́nez-Bazán, C.; Gordillo, José Manuel

doi:10.1063/1.3009298

Cited by 50 publications

(60 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Manasseh et al (1998) and Bolanos-Jiménez et al (2008) experimentally showed that this process also creates high speed jets. Indeed, as the bubble grows in size, the neck becomes more and more elongated and, eventually, surface tension triggers the pinch-off of the bubble, leading to the formation of two fast and small jets as illustrated in figure 3.…”

Section: Bubble Pinch-off From An Underwater Nozzlementioning

confidence: 99%

“…For the quasi-static injection conditions considered here, the relevant dimensionless parameter characterizing this physical situation is the Bond number Bo = ρR 2 N g/σ [Longuet-Higgins et al (1991); Bolanos-Jiménez et al (2008)], which in the case presented here equals 2.1. More details of our simulation method are given in Oguz & Prosperetti (1993); Gekle et al (2009c).…”

Section: Bubble Pinch-off From An Underwater Nozzlementioning

confidence: 99%

“…Instead, the description of this type of jets shares many similarities with the very violent jets of fluidized metal which are ejected after the explosion of lined cavities [e.g. Birkhoff et al (1948)], with those formed when an axisymmetric bubble collapses inside a stagnant liquid pool [Manasseh et al (1998); Bolanos-Jiménez et al (2008)] or possibly even with the granular jets observed when an object impacts a fluidized granular material [Thoroddsen & Shen (2001); Lohse et al (2004)]. …”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Generation and breakup of Worthington jets after cavity collapse. Part 1. Jet formation

2010

Self Cite

View full text Add to dashboard Cite

At the beginning of the last century Worthington and Cole discovered that the high-speed jets ejected after the impact of an axisymmetric solid on a liquid surface are intimately related to the formation and collapse of an air cavity created in the wake of the impactor. In this paper, we combine detailed boundary-integral simulations with analytical modelling to describe the formation of such Worthington jets after the impact of a circular disk on water. We extend our earlier model in Gekle et al. (Phys. Rev. Lett., vol. 102, 2009a, 034502), valid for describing only the jet base dynamics, to describe the whole jet. We find that the flow structure inside the jet may be divided into three different regions: the axial acceleration region, where the radial momentum of the incoming liquid is converted to axial momentum; the ballistic region, where fluid particles experience no further acceleration and move constantly with the velocity obtained at the end of the acceleration region; and the jet tip region, where the jet eventually breaks into droplets. From our modelling of the ballistic region we conclude that, contrary to the case of other physical situations where high-speed jets are also ejected, the types of Worthington jets studied here cannot be described using the theory of hyperbolic jets of Longuet-Higgins (J. Fluid Mech., vol. 127, 1983, p. 103). Most importantly, we find that the velocity and the shape of the ejected jets can be well predicted at any instant in time with the only knowledge of quantities obtained before pinch-off occurs. This fact allows us to provide closed expressions for the jet velocity and the sizes of the ejected droplets as a function of the velocity and the size of the impactor. We show that our results are also applicable to Worthington jets emerging after the collapse of a bubble growing from an underwater nozzle, although this system creates thicker jets than the disk impact.

show abstract

Section: Bubble Pinch-off From An Underwater Nozzlementioning

confidence: 99%

Section: Bubble Pinch-off From An Underwater Nozzlementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Generation and breakup of Worthington jets after cavity collapse. Part 1. Jet formation

2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…In all these cases jetting seems thus to be accomplished by a mechanism different from the one in this Letter. In the case of drop impact [15,16] or gas injection through a needle [3,17], however, the formation of a cavity and its subsequent inertial collapse can sometimes be observed and the present mechanism might be of relevance.Our experimental setup consists of a circular disc with radius R 0 that is pulled through a water surface with velocity V 0 as described in [4]. The velocity V 0 is kept constant throughout the whole process.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

High-Speed Jet Formation after Solid Object Impact

Gekle

Gordillo

Meer

et al. 2009

Computational Fluid Dynamics 2008

View full text Add to dashboard Cite

A circular disc hitting a water surface creates an impact crater which after collapse leads to a vigorous jet. Upon impact an axisymmetric air cavity forms and eventually pinches off in a single point halfway down the cavity. Two fast sharp-pointed jets are observed shooting up-and downwards from the closure location, which by then has turned into a stagnation point surrounded by a locally hyperbolic flow pattern. This flow, however, is not the mechanism feeding the jets. Using high-speed imaging and numerical simulations we show that jetting is fed by the local flow around the base of the jet, which is forced by the colliding cavity walls. We show how the well-known theory of a collapsing void (using a line of sinks on the symmetry axis) can be continued beyond pinch-off to obtain a new and quantitative model for jet formation which agrees well with numerical and experimental data. DOI: 10.1103/PhysRevLett.102.034502 PACS numbers: 47.55.NÀ, 47.11.Hj, 47.55.DÀ, 47.55.df The most prominent phenomenon when a solid object hits a water surface is the high-speed jet shooting upwards into the air. The basic sequence of events leading to this jet has been studied since Worthington over a century ago: After impact, the intruder creates an air-filled cavity in the liquid which due to hydrostatic pressure immediately starts to collapse, eventually leading to the pinch-off of a large bubble. Two very thin jets are ejected up-, respectively, downwards from the pinch-off point. This finite-time singularity has been intensively studied in recent time [1][2][3][4][5]. Such singularities have been shown to lead to a hyperbolic flow pattern after collapse and thus to the formation of liquid jets [6][7][8][9].As we show in the present work, however, the radial energy focusing towards the singular pinch-off point alone is not sufficient to explain the extreme thinness of jets observed after the impact of a solid object. Instead, this jet formation is shown to depend crucially on the kinetic energy contained in the entire collapsing wall of the cavity even far above the pinch-off singularity. This is in contrast to jets observed in many other situations where narrow confining cavity walls are not present, e.g., for bubbles bursting on a free surface or near a solid wall [9][10][11], wave focusing [12,13], or jets induced by pressure waves [14]. In addition, surface tension in our case turns out to be irrelevant in contrast to capillary-driven scenarios as suggested for Faraday waves [7,8]. In all these cases jetting seems thus to be accomplished by a mechanism different from the one in this Letter. In the case of drop impact [15,16] or gas injection through a needle [3,17], however, the formation of a cavity and its subsequent inertial collapse can sometimes be observed and the present mechanism might be of relevance.Our experimental setup consists of a circular disc with radius R 0 that is pulled through a water surface with velocity V 0 as described in [4]. The velocity V 0 is kept constant throughout the whole process. Globa...

show abstract

Bubble formation and dynamics in a quiescent high‐density liquid

et al. 2015

View full text Add to dashboard Cite

Gas bubble formation from a submerged orifice under constant-flow conditions in a quiescent high-density liquid metal, lead-bismuth eutectic (LBE), at high Reynolds numbers was investigated numerically. The numerical simulation was carried out using a coupled level-set and volume-of-fluid method governed by axisymmetric Navier-Stokes equations. The ratio of liquid density to gas density for the system of interest was about 15,261. The bubble formation regimes varied from quasi-static to inertia-dominated and the different bubbling regimes such as period-1 and period-2 with pairing and coalescence were described. The volume of the detached bubble was evaluated for various Weber numbers, We, at a given Bond number, Bo, with Reynolds number Re ) 1. It was found that at high values of the Weber number, the computed detached bubble volumes approached a 3/5 power law. The different bubbling regimes were identified quantitatively from the time evolution of the growing bubble volume at the orifice. It was shown that the growing volume of two consecutive bubbles in the period-2 bubbling regime was not the same whereas it was the same for the period-1 bubbling regime. The influence of grid resolution on the transition from period-1 to period-2 with pairing and coalescence bubbling regimes was investigated. It was observed that the transition is extremely sensitive to the grid size. The transition of period-1 and period-2 with pairing and coalescence is shown on a Weber-Bond numbers map. The critical value of Weber number signalling the transition from period-1 to period-2 with pairing and coalescence decreases with Bond number as We $ Bo 21 , which is shown to be consistent with the scaling arguments. Furthermore, comparisons of the dynamics of bubble formation and bubble coalescence in LBE and water systems are discussed. It was found that in a high Reynolds number bubble formation regime, a difference exists in the transition from period-1 to period-2 with pairing and coalescence between the bubbles formed in water and the bubbles formed in LBE. V C 2015 American Institute of Chemical Engineers AIChE J, 61: 3996-4012, 2015

show abstract

Axisymmetric bubble collapse in a quiescent liquid pool. II. Experimental study

Cited by 50 publications

References 18 publications

Generation and breakup of Worthington jets after cavity collapse. Part 1. Jet formation

Generation and breakup of Worthington jets after cavity collapse. Part 1. Jet formation

High-Speed Jet Formation after Solid Object Impact

Bubble formation and dynamics in a quiescent high‐density liquid

Contact Info

Product

Resources

About