A granular Rayleigh-Taylor instability: experiments and simulations
نویسندگان
چکیده
A granular instability is studied experimentally and numerically as a packing of dense granular material positioned above a gap of air falls under gravity in a closed Hele-Shaw cell; a granular analog of the RayleighTaylor instability. A characteristic pattern of fingers separated by dilute bubbles emerges along the interface, and, in contrast to the classical, hydrodynamic instability, a transient coarsening of the front is observed. The emerging structures are quantified by means of Fourier analysis and quantitative agreement between experiment and computation is shown. This analysis also reveals scale invariance of the flow structures under overall change of spatial scale.
منابع مشابه
Granular Rayleigh-Taylor instability: experiments and simulations.
A granular instability driven by gravity is studied experimentally and numerically. The instability arises as grains fall in a closed Hele-Shaw cell where a layer of dense granular material is positioned above a layer of air. The initially flat front defined by the grains subsequently develops into a pattern of falling granular fingers separated by rising bubbles of air. A transient coarsening ...
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