Velocity field distributions due to ideal line vortices
Abstract
We evaluate numerically the velocity field distributions produced by a bounded, two-dimensional fluid model consisting of a collection of parallel ideal line vortices. We sample at many spatial points inside a rigid circular boundary. We focus on ``nearest neighbor'' contributions that result from vortices that fall (randomly) very close to the spatial points where the velocity is being sampled. We confirm that these events lead to a non-Gaussian high-velocity ``tail'' on an otherwise Gaussian distribution function for the Eulerian velocity field. We also investigate the behavior of distributions that do not have equilibrium mean-field probability distributions that are uniform inside the circle, but instead correspond to both higher and lower mean-field energies than those associated with the uniform vorticity distribution. We find substantial differences between these and the uniform case.
Cite
@article{arxiv.physics/0102058,
title = {Velocity field distributions due to ideal line vortices},
author = {Thomas S. Levi and David C. Montgomery},
journal= {arXiv preprint arXiv:physics/0102058},
year = {2009}
}
Comments
21 pages, 9 figures. To be published in Physical Review E (http://pre.aps.org/) in May 2001