Volume 84, Number 4, November 2008
Article Number 44002
Number of page(s) 6
Section Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics
Published online 12 November 2008
EPL, 84 (2008) 44002
DOI: 10.1209/0295-5075/84/44002

Jamming and critical outlet size in the discharge of a two-dimensional silo

A. Janda1, I. Zuriguel1, A. Garcimartín1, L. A. Pugnaloni2 and D. Maza1

1   Departamento de Física y Matemática Aplicada, Universidad de Navarra - 31080 Pamplona, Spain, EU
2   Instituto de Física de Líquidos y Sistemas Biológicos (CONICET-UNLP-CIC) - Casilla de correo 565, 1900 La Plata, Argentina

received 20 June 2008; accepted in final form 13 October 2008; published November 2008
published online 12 November 2008

We present an experimental study of jamming in the discharge of grains through an opening in a two-dimensional silo. For a wide range of outlet sizes, we obtain the size distribution of avalanche defined as the number of grains that fall between two consecutive jams. From these distributions, we obtain the probability that the silo jams before N particles pass through the orifice. Then a simple model of arch formation is proposed that predicts the shape of the jamming probability function and reveals that it does not exist a critical size of the orifice above which there is not jamming.

47.57.Gc - Granular flow.
45.70.Vn - Granular models of complex systems; traffic flow.

© EPLA 2008