Berlin 2012 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

DY: Fachverband Dynamik und Statistische Physik

DY 29: Posters II

DY 29.52: Poster

Thursday, March 29, 2012, 17:00–19:00, Poster A

Measuring the configurational temperature in a binary disc packing — •Song-Chuan Zhao and Matthias Schröter — Max-Planck-Institute for Dynamics and Self-Organization, Göttingen,Germany

A statistic mechanics of granular packing has been suggested by analogy to thermodynamic systems [1]. A configurational temperature, called compactivity, is defined as ∂V/∂S. The measurement of the compactivity plays an important role in testing the validity of this theory. A method to measure X is suggested as following: if the Volume probability distribution is Boltzmann like, then the ratio of two overlapping distributions at different configurational temperatures should be exponential. An extension of this method can be used to measure the entropy in a granular packing. McNamara and coworkers apply this method to sphere packing and conclude that the distribution of Voronoi volumes obeys the theoretical prediction [2].

Recently we have found that there are correlations between Voronoi volumes in disc packing [3]. These correlations raise the question on which scale a configurational temperature can be defined uniformly. We present the compactivity measurement of a bi-disperse disc system and show that the compactivity is uniform above a certain scale.

[1] S.F. Edwards and R.B.S. Oakeshott, Physica A, 157 1080 (1989)

[2] Sean McNamara, Patrick Richard, Sbastien Kiesgen de Richter, Grand Le Car and Renaud Delannay, Phys. Rev. E, 80 031301 (2009)

[3] Song-Chuan Zhao, Stacy Sidle, Harry L. Swinney and Matthias Schröter, arXiv:1109.0935