Resonant acoustic propagation and negative density in liquid foams.
نویسندگان
چکیده
We measured the dispersion relation for acoustic longitudinal waves in liquid foams, over a broad frequency range (60-600 kHz). Strong dispersion was found, with two nondispersive behaviors, separated by a negative density regime. A new model, based on the coupled displacements of films, liquid channels, and gas in the foam, rationalizes all the experimental findings.
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ورودعنوان ژورنال:
- Physical review letters
دوره 112 14 شماره
صفحات -
تاریخ انتشار 2014