Reverse Brazil nut problem: competition between percolation and condensation.
نویسندگان
چکیده
In the Brazil nut problem (BNP), hard spheres with larger diameters rise to the top. There are various explanations (percolation, reorganization, convection), but a broad understanding or control of this effect is by no means achieved. A theory is presented for the crossover from BNP to the reverse Brazil nut problem based on a competition between the percolation effect and the condensation of hard spheres. The crossover condition is determined, and theoretical predictions are compared to molecular dynamics simulations in two and three dimensions.
منابع مشابه
Reversing the Brazil-nut effect: competition between percolation and condensation.
We report on experiments on vertically shaken binary granular mixtures, which separate into their components due to the external excitation. This well-known phenomenon, where large particles rise to the top of the mixture, is called the Brazil-nut effect. Recent theoretical findings predict also a reverse Brazil-nut effect, where large particles sink to the bottom of the container. We choose sp...
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In a recent paper [1] the Brazil nut problem (BNP), where particles with large diameters rise to the top when exposed to vertical shaking and the reverse Brasil nut problem (RBNP) where the large particles segregate to the bottom were investigated. In realistic situations these effects are driven or at least accompanied by global convection. Convection rolls are observed already in mono-dispers...
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ورودعنوان ژورنال:
- Physical review letters
دوره 86 15 شماره
صفحات -
تاریخ انتشار 2001