Brazil-nut effect: Size separation of granular particles
Abstract
Granular media differ from other materials in their response to stirring or jostling - unlike two-fluid systems, bi-disperse granular mixtures will separate according to particle size when shaken, with large particles rising, a phenomenon termed the 'Brazil-nut effect'. Mounting evidence indicates that differences in particle density affect size separation in mixtures of granular particles. We show here that this density dependence does not follow a steady trend but is non-monotonic and sensitive to background air pressure. Our results indicate that particle density and interstitial air must both be considered in size segregation.
- Publication:
-
Nature
- Pub Date:
- November 2001
- DOI:
- 10.1038/35104697
- Bibcode:
- 2001Natur.414..270M