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Title: Instability of trajectories of solid particles around vortex lines

Abstract

Progress in implementing the particle image velocimetry visualization technique in liquid helium has stimulated interest in understanding the dynamics of micron-size solid particles in a superfluid. We show that at sufficiently low temperatures, in the limit of a pure superfluid, the trajectories of small, neutrally buoyant, solid particles are unstable and deviate from the trajectories of superfluid particles, even in the simplest case of the motion around a single stationary straight vortex line. The result also applies to classical Euler flows. The implications of this result for the visualization of turbulent superflow at very low temperatures are discussed.

Authors:
 [1]; ;  [2];  [3]
  1. School of Mechanical and Systems Engineering, University of Newcastle, Newcastle upon Tyne, NE1 7RU (United Kingdom)
  2. School of Mathematics, University of Newcastle, Newcastle upon Tyne, NE1 7RU (United Kingdom)
  3. School of Physics, University of Birmingham, Birmingham, B15 2TT (United Kingdom)
Publication Date:
OSTI Identifier:
20787903
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevB.73.052502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; FLOW VISUALIZATION; HELIUM; HELIUM 4; IMAGES; INSTABILITY; LIQUIDS; PARTICLES; SOLIDS; SUPERFLUIDITY; TEMPERATURE DEPENDENCE; TURBULENCE; VORTICES

Citation Formats

Sergeev, Y. A., Barenghi, C. F., Kivotides, D., and Vinen, W. F.. Instability of trajectories of solid particles around vortex lines. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.0.
Sergeev, Y. A., Barenghi, C. F., Kivotides, D., & Vinen, W. F.. Instability of trajectories of solid particles around vortex lines. United States. doi:10.1103/PHYSREVB.73.0.
Sergeev, Y. A., Barenghi, C. F., Kivotides, D., and Vinen, W. F.. Wed . "Instability of trajectories of solid particles around vortex lines". United States. doi:10.1103/PHYSREVB.73.0.
@article{osti_20787903,
title = {Instability of trajectories of solid particles around vortex lines},
author = {Sergeev, Y. A. and Barenghi, C. F. and Kivotides, D. and Vinen, W. F.},
abstractNote = {Progress in implementing the particle image velocimetry visualization technique in liquid helium has stimulated interest in understanding the dynamics of micron-size solid particles in a superfluid. We show that at sufficiently low temperatures, in the limit of a pure superfluid, the trajectories of small, neutrally buoyant, solid particles are unstable and deviate from the trajectories of superfluid particles, even in the simplest case of the motion around a single stationary straight vortex line. The result also applies to classical Euler flows. The implications of this result for the visualization of turbulent superflow at very low temperatures are discussed.},
doi = {10.1103/PHYSREVB.73.0},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 5,
volume = 73,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2006},
month = {Wed Feb 01 00:00:00 EST 2006}
}
  • The dynamics of curved vortex filaments is studied analytically and numerically in the framework of a three-dimensional complex Ginzburg-Landau equation (CGLE). It is shown that a straight vortex line is unstable with respect to spontaneous stretching and bending in a substantial range of parameters of the CGLE, resulting in formation of persistent entangled vortex configurations. The boundary of the three-dimensional instability in parameter space is determined. Near the stability boundary, the supercritical saturation of the instability is found, resulting in the formation of stable helicoidal vortices. {copyright} {ital 1998} {ital The American Physical Society}
  • The dynamics of curved vortex filaments is studied analytically and numerically in the framework of a three-dimensional complex Ginsburg-Landau equation (CGLE). It is proved that a straight vortex line is unstable with respect to spontaneous stretching and bending in a certain range of parameters of the CGLE, resulting in formation of persistent entangled vortex configurations. The analysis shows that the standard approach relating the velocity of the filament with the local curvature is insufficient to describe the instability and stretching of vortex lines.
  • The dynamics of curved vortex filaments is studied analytically and numerically in the framework of a three-dimensional complex Ginzburg-Landau equation (CGLE). It is shown that a straight vortex line is unstable with respect to spontaneous stretching and bending in a substantial range of parameters of the CGLE, resulting in formation of persistent entangled vortex configurations. The boundary of the three-dimensional instability in parameter space is determined. Near the stability boundary, the supercritical saturation of the instability is found, resulting in the formation of stable helicoidal vortices.
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