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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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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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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 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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Vortex breakdown in spherical gap
The Physics of Fluids, 1987A finite element solution of the flow between rotating spheres shows a vortex breakdown for Reynolds numbers exceeding a critical value. The result is in agreement with published results for a vortex breakdown in a cylindrical enclosure.
P. Bar-Yoseph +3 more
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Numerical study of vortex breakdown
24th Aerospace Sciences Meeting, 1986The incompressible axisymmetric steady Navier-Stokes equations and the Euler equations are solved numerically to model the breakdown of a vortex. The solutions obtained for the Euler equations show a 'vortex breakdown-like' structure, their behavior is very different from that of the Navier-Stokes solutions which are obtained at low Reynolds number ...
Hafez, M., Kuruvila, G., Salas, M. D.
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Vortex Breakdown in Swirling Conical Flows
AIAA Journal, 1971This paper describes some experiments in swirling flows in a mildly diverging cylindrical tube in which three types of vortex breakdown were observed: double-helix and spiral forms (followed by turbulent mixing), and axisymmetric form (often followed by a spiral breakdown, then by turbulent mixing). The type and location of the breakdowns were found to
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Research into vortex breakdown control
Progress in Aerospace Sciences, 2001Abstract Vortex breakdown remains a significant and intriguing phenomenon that can have detrimental or beneficial effects, depending on the application. Thus there is a strong need to both better understand the phenomenon and to control it, either to prevent breakdown or to promote it.
Anthony M Mitchell, Jean Délery
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Abstract A thin vortex tube can undergo a sudden expansion, often leading to instability and turbulence, if subject to an external deceleration. This is called vortex breakdown, and it is often observed in swirling flow in a slowly diverging pipe, and in the scroll vortices that develop on the upper surface of a delta wing.
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Computational Studies of Vortex Breakdown
1992Abstract : Axisymmetric vortex breakdown was simulated numerically within an enclosed circular cylinder with: (1) fixed cylindrical wall-endwall and one rotating lid; and (2) rotating cylindrical wall-endwall with a differentially rotating lid. Variations of the two dynamical parameters permitted the calculation of cases in which incipient vortex ...
John P. Watson, G. P. Neitzel
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