Effects of axial flow on the stability of a helical vortex tube

Y. Hattori, Yasuhide Fukumoto

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The effects of axial flow on the stability of a helical vortex tube are studied by short-wavelength stability analysis. By axial flow we mean the flow along the helical tube inside the vortex core. At the leading order the base flow is set to the Rankine vortex with uniform velocity along the helical tube. The exponential growth rate is obtained analytically as the magnitude of the sum of three O(ε) and five O(ε2) complex numbers, where ε is the ratio of the core to curvature radius. At O(ε) the effect of axial flow can be regarded as the effect of the Coriolis force; as a result the instability is the superposition of the curvature instability and the Coriolis or precessional instability since the two instabilities occur under the same resonance condition. At O(ε2) combined effects of the axial flow and the torsion appear; the maximum growth rate increases when the period of particle motion increases.

Original languageEnglish
Article number054102
JournalPhysics of Fluids
Volume24
Issue number5
DOIs
Publication statusPublished - May 1 2012

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vortex tubes
axial flow
curvature
vortices
tubes
complex numbers
base flow
particle motion
torsion
radii
wavelengths

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics

Cite this

Effects of axial flow on the stability of a helical vortex tube. / Hattori, Y.; Fukumoto, Yasuhide.

In: Physics of Fluids, Vol. 24, No. 5, 054102, 01.05.2012.

Research output: Contribution to journalArticle

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