Journal ArticleDOI
Experiments on vortex stability
TLDR
In this paper, the tip vortex of a laminar flow wing was studied at a sectional lift-to-drag ratio of 60.8×104, where Γ is the total circulation and ν is the kinematic viscosity.Abstract:
The tip vortex of a laminar flow wing was studied at a sectional lift‐to‐drag ratio of 60. The vortex Reynolds number was Γ0/ν=7.8×104, where Γ0 is the total circulation and ν is the kinematic viscosity. At and near the wing the vortex core was turbulent with an axial jet. Downstream of the wing the jet rapidly dissipated and a wake developed in the core and intensity of turbulent velocities decreased. From 13 to 40 chord length periodic oscillations dominated the velocity fluctuations with little background turbulence. These instabilities had a symmetric and a helical mode with wavelength of the same order as the core diameter. In this range of distances along the vortex core the maximum axial, swirl, and fluctuating velocities vary slowly. At 40 chord lengths behind the wing there is a rapid change in these velocities. This change of state of the vortex core is accompanied by change of velocity fluctuations from periodic to turbulent. The core showed spatial excursions. Measurements up to 80 chord lengths downstream showed no self‐similar decay.read more
Citations
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Journal ArticleDOI
The structure of vortex breakdown
TL;DR: In this article, the authors present a survey of vortex breakdown, which is a disturbance characterized by the formation of an internal stagnation point on the vortex axis, followed by reversed flow in a region of limited axial extent.
Journal ArticleDOI
Vortex stability and breakdown - Survey and extension
TL;DR: In this article, the authors analyse theorique et experimentale des conditions de stabilite and d'eclatement de tourbillons isoles incompressible for des valeurs elevees du nombre de Reynolds.
Journal ArticleDOI
The structure and development of a wing-tip vortex
TL;DR: In this article, a theory was developed to correct mean-velocity profiles for the effects of wandering and to provide complete quantitative estimates of its amplitude and contributions to Reynolds stress fields.
Journal ArticleDOI
Airplane trailing vortices
TL;DR: A review of the formation, motion, and persistence of trailing vortices is presented in this article, which highlights findings or shifts made since Widnall's (1975) review in this series.
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A sufficient condition for the instability of columnar vortices
TL;DR: In this paper, the inviscid instability of columnar vortex flows in unbounded domains to three-dimensional perturbations is considered and a sufficient condition for columnar vortices is formulated.
References
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Journal ArticleDOI
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The stability of a trailing line vortex. Part 1. Inviscid theory
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Slender-body analysis of the motion and stability of a vortex filament containing an axial flow
TL;DR: In this article, the effect of axial flow on the stability of a single vortex filament and a pair of vortices has been investigated and the stability boundary has been obtained.
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Stability of Coaxial Rotating Jet and Vortex of Different Densities
TL;DR: In this paper, the stability of a rotating axisymmetric jet surrounded by a potential vortex to infinitesimal disturbances in the inviscid incompressible fluid approximation is considered.