Enstrophy cascades in two-dimensional dense granular flows

Kuniyasu Saitoh, Hideyuki Mizuno

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

Abstract

Employing two-dimensional molecular dynamics simulations of dense granular materials under simple shear deformations, we investigate vortex structures of particle rearrangements. Introducing vorticity fields as a measure of local spinning motions of the particles, we observe their heterogeneous distributions, where statistics of vorticity fields exhibit the highly non-Gaussian behavior and typical domain sizes of vorticity fields significantly increase if the system is yielding under quasistatic deformations. In such dense granular flows, a power-law decay of vorticity spectra can be observed at mesoscopic scale, implying anomalous local structures of kinetic energy dissipation. We explain the power-law decay, or enstrophy cascades in dense granular materials, by a dimensional analysis, where the dependence of vorticity spectra not only on the wave number, but also on the shear rate, is well explained. From our dimensional analyses, the scaling of granular temperature and rotational kinetic energy is also predicted.

Original languageEnglish
Article number022908
JournalPhysical Review E
Volume94
Issue number2
DOIs
Publication statusPublished - 2016 Aug 31

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Enstrophy cascades in two-dimensional dense granular flows'. Together they form a unique fingerprint.

Cite this