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The Jamming Transition in Granular Systems

T. S. Majmudar·M. Sperl·S. Luding·R. P. Behringer
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Abstract

Recent simulations have predicted that near jamming for collections of spherical particles, there will be a discontinuous increase in the mean contact number, Z, at a critical volume fraction, phi_c. Above phi_c, Z and the pressure, P are predicted to increase as power laws in phi-phi_c. In experiments using photoelastic disks we corroborate a rapid increase in Z at phi_c and power-law behavior above phi_c for Z and P. Specifically we find power-law increase as a function of phi-phi_c for Z-Z_c with an exponent beta around 0.5, and for P with an exponent psi around 1.1. These exponents are in good agreement with simulations. We also find reasonable agreement with a recent mean-field theory for frictionless particles.

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T. S. Majmudar, M. Sperl, S. Luding, R. P. Behringer. 2006-12-18. The Jamming Transition in Granular Systems. https://doi.org/10.1103/physrevlett.98.058001

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