Bubble avalanches

Actually, avalanches of popping bubbles were put in evidence during the coarsening of bidimensional and three-dimensional aqueous foams (Ritacco et ah, 2007 Vandewalle et ah, 2001). How does the bubble raft behave at the surface of a flute poured with champagne Does a bursting... 

Ritacco, H., Kiefer, F., and Langevin, D. (2007). Lifetime of bubble rafts Cooperativity and avalanches. Phys. Rev. Lett. 98, 244501. 

Vandewalle, N., Lentz, J.-F., Dorbolo, S., and Brisbois, F. (2001). Avalanches of popping bubbles in collapsing foams. Phys. Rev. Lett. 86,179-182. 

These pressures are clearly seen in Fig. 6.14, plotted for a foam from silicon-organic compounds. For a Triton-X-100 foam (Fig. 6.13) a weak decrease in the rp(Ap) dependence is also observed within the range of pressure drops higher than 10 kPa. The avalanche-like destruction occurs after a period of some minutes, i.e. after a certain change in the initial dispersity, and probably, after a bubble distribution by size that influences the process of structural rearrangement. 

Thus, on the one hand, the foam film type (and therefore the type of stabilisation due to long-range and short-range forces) is the determining factor for the course of tp(Ap0) dependences. On the other hand, in some systems an avalanche-like destruction occurs at A/ cr. A reasonable question arises as to why a foam built up of different types of foam films destructs before reaching Aplr. If the foam is considered as a system built up of equilibrium foam films, then they should be infinitely stable. However, the foam is a more complex system, built up of foam films and borders, subjected to the effect of several other factors (gas diffusion transfer, coalescence of bubbles and changes in the foam film size, external actions, local stretching, collective effects of destruction, etc.) which can lead to its destruction. 

It was pointed out that measurements of laser-induced breakdown suffer from the same artifacts as DC-breakdown measurements. Impurities of low ionization energy, submicroscopic particles (dust or ice), and microscopic gas bubbles may serve as centers for the initiation of the breakdown process and mask the development of a pure avalanche breakdown (Brueck and Kildal, 1981). Subsequent investigations on the optical breakdown of liquid helium (Abrikosova and Anshukov, 1973 ... 

In agreement with the described model the breakdown may expand rapidly with the expansion of vapor bubbles as the avalanche charge multiplication process starts within the vapor phase and not in the liquid phase [cf. Section II.2(iii)]. 

Durian proposed a model [129-131] for slip avalanches in wet, disordered foams at nonzero shear rate. His model treats the foam as consisting of spherical bubbles that can overlap, where the overlap determines the pairwise repulsive interactions between neighboring bubbles. The model also contains a viscous... 

D. J. Durian. Bubble-scale model of foam mechanics Melting nonlinear behavior and avalanches. Phys. Rev. E 55,1739-1751 (1997). 

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