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Anomalous diffusion in a randomly modulated velocity field
by Noriaki Aibara, Naoaki Fujimoto, So Katagiri, Yutaka Matsuo, Yoshiki Matsuoka, Akio Sugamoto, Ken Yokoyama, Tsukasa Yumibayashi
Submission summary
Ontological classification |
Academic field: |
Physics |
Specialties: |
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Approaches: |
Theoretical, Computational |
Abstract
This paper proposes a simple model of anomalous diffusion, in which a particle moves with the velocity field induced by a single "dipole" (a doublet or a pair of source and sink), whose moment is modulated randomly at each time step. A motivation to introduce such a model is that it may serve as a toy model to investigate an anomalous diffusion of fluid particles in turbulence. We perform a numerical simulation of the fractal dimension of the trajectory using periodic boundary conditions in two and three dimensions. For a wide range of the dipole moment, we estimate the fractal dimension of the trajectory to be 1.7--1.9 (2D) and 2.4--2.7 (3D).