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arXiv · 0904.2305

Approach to Universality in Axisymmetric Bubble Pinch-Off

Stephan Gekle·Devaraj van der Meer·Jacco H. Snoeijer·Detlef Lohse
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Abstract

The pinch-off of an axisymmetric air bubble surrounded by an inviscid fluid is compared in four physical realizations: (i) cavity collapse in the wake of an impacting disc, (ii) gas bubbles injected through a small orifice, (iii) bubble rupture in a straining flow, and (iv) a bubble with an initially necked shape. Our boundary-integral simulations suggest that all systems eventually follow the universal behavior characterized by slowly varying exponents predicted in [Eggers et al., PRL 98, 094502 (2007)]. However, the time scale for the onset of this final regime is found to vary by orders of magnitude depending on the system in question: while for the impacting disc it is well in the millisecond range, for the gas injection needle universal behavior sets in only a few microseconds before pinch-off. These findings reconcile the different views expressed in recent literature about the universal nature of bubble pinch-off.

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Stephan Gekle, Devaraj van der Meer, Jacco H. Snoeijer, Detlef Lohse. 2009-04-15. Approach to Universality in Axisymmetric Bubble Pinch-Off. https://doi.org/10.1103/physreve.80.036305

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