Date/Time
Date(s) - 14/03/2007
3:30 pm - 4:30 pm

Title: Patterns in the Sand: The Physics of Granular Flow

Speaker: Dr. Tom Mullin

Institute: University of Manchester

Location: ABB 102

Description:

Segregation of mixtures of granular materials is a topic which is of interest to a broad range of scientists from physicists, to geologists and engineers. An everyday occurrence the phenomenon can be seen at the breakfast table, where the fruit and nuts are usually found clustered at the top of a packet of muesli. The process can be driven by either simple avalanching in binary mixtures when the angle of repose of the constituents are different, or it can be promoted using an external drive or perturbation. We will discuss these issues and present the results of a new experimental study of particle segregation in a binary mixture, which is subject to a periodic horizontal forcing. A surprising self-organization process is observed which shows critical behavior in its formation. Connections with concepts from equilibrium phase transitions will be discussed.