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The evolution of a perturbed vortex in a pipe to axisymmetric vortex breakdown
Journal of Fluid Mechanics, 1998The evolution of a perturbed vortex in a pipe to axisymmetric vortex breakdown is studied through numerical computations. These unique simulations are guided by a recent rigorous theory on this subject presented by Wang & Rusak (1997a). Using the unsteady and axisymmetric Euler equations, the nonlinear dynamics of both small- and large ...
Rusak, Z., Wang, S., Whiting, C. H.
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On the interpretation of vortex breakdown
Physics of Fluids, 1995Studying the numerous papers that have appeared in the recent past that address ‘‘vortex breakdown,’’ it may be difficult for a reader to avoid getting rather confused. It appears that various authors or even schools have conflicting views on the correct interpretation of the physics of vortex breakdown. Following the investigation by Keller et al. [Z.
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Simple numerical criterion for vortex breakdown
AIAA Journal, 1992Vortex breakdown is currently identified in numerical flow solutions through postprocessing techniques. Although these methods can identify breakdown accurately, they can involve cumbersome data transfer and processing that can be quite time consuming. Therefore, a simple Rossby number criterion is proposed. The criterion is established using solutions
Robinson, B. A. +2 more
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The Structure of Vortex Breakdown
Annual Review of Fluid Mechanics, 1978The term 'vortex breakdown', as used in the reported investigation, refers to 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. Two forms of vortex breakdown, which predominate, are shown in photographs.
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On Vortex Breakdown and Instability.
1981Abstract : Solutions of the full steady axisymmetric Navier-Stokes equations for breakdown in an unconfined viscous vortex have been obtained by Grabowski and Berger. The core Reynolds numbers were varied up to 200 and a two-parameter family of velocity distributions was assumed upstream as the boundary condition. In this report, the Richardson numbers
Wilbur L. Hankey, Shiva N. Singh
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Disrupted states of vortex flow and vortex breakdown
The Physics of Fluids, 1977Flow visualization studies and laser Doppler anemometer measurements on swirling water flows reveal six distinct types of very large amplitude disturbance modes of the vortex core. Three, ’’axisymmetric’’ and spiral vortex breakdowns, and the ’’double helix,’’ have been described by others.
J. H. Faler, S. Leibovich
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Inviscid swirling flows and vortex breakdown
Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences, 1995Abstract The steady axisymmetric Euler flow of an inviscid incompressible swirling fluid is described exactly by the Squire–Long equation. This equation is studied numerically for the case of diverging flow to investigate the dependence of solutions on upstream, or inlet, and downstream, or outlet, boundary conditions and flow ...
Buntine, James D., Saffman, Philip G.
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Vortex development and breakdown
8th Fluid and PlasmaDynamics Conference, 1975Abstract : A line vortex is assumed to consist of a thin viscous core of laminar embedded in an inviscid flow of uniform circulation and with axial velocity that may depend upon the distance along the core. Self-similar solutions are obtained for the particular case of an external velocity inversely proportional to the core length.
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Progress in Aerospace Sciences, 1994
Abstract Vortex breakdown is of primary importance in many situations met in aeronautical as well as extra-aeronautical applications. During the past 40 years, this problem has been the subject of a large number of investigations, both in the experimental and theoretical domains.
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Abstract Vortex breakdown is of primary importance in many situations met in aeronautical as well as extra-aeronautical applications. During the past 40 years, this problem has been the subject of a large number of investigations, both in the experimental and theoretical domains.
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Vortex breakdown as a fundamental element of vortex dynamics
Fluid Dynamics Research, 1988zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Keller, J. J., Egli, W., Althaus, R.
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