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Showing 1 to 13 of 13 for “"Vortex Sheets"”.
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Vorticity and vortex sheets in axial turbomachines
Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Mechanical Engineering, 1954.
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Two cylindrical vortex sheets : evolution and singularity formation
Using Rosenhead's point-vortex approximation with correction terms, the evolution of two symmetrical, counter-rotating, initially cylindrical vortex sheets in an incompressible, potential fluid flow is studied. Simulations are performed in time up to the occurrence of branch-point curvature …
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Understanding Vortex Reconnection in Complex Fluid Flows
… the reconnection process for three initial vortex tube set-ups; anti-parallel, orthogonal and anti-parallel with axial flow. From these we are able to identify each of the different reconnection processes observed and discussed for the magnetic reconnection case but not necessarily the …
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Phase transitions in lattice gauge theories
… function is represented as a sum over world-sheets of gauge-invariant ""vortex"" sheets. The phase transition of the system is then related to the condensation of these excitations via standard energy-entropy arguments. Results of Monte Carlo simulations are then presented. The density of the …
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Separation and wakes over three-dimensional bodies
… of three-dimensional separation. The Vortex-Lattice method was employed to calculate the inviscid flow and the development of separated vortex sheets over a prolate spheroid. An approximate-method based on the assumption of local similarity was used to solve the boundary layer …
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Application of panel methods for subsonic aerodynamics
… flows. The lifting surface is modelled with a vortex sheet and the wakes by discrete vortices. As an imitation of the conditions at the trailing edge, stagnation conditions on both surfaces are used. The over-determined system is solved by an optimization scheme. The present predictions are in …
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Radar observations of misovortices within multiple long-lake-axis-parallel lake-effect bands during the OWLeS project
… shear along these convergence zones yields vortex sheets that can break into discrete misovortices, likely through horizontal shearing instability (HSI). These misovortices then can strengthen or be maintained via stretching by the band updrafts. Recent analysis of a single case from OWLeS …
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Simulations of a self propelled autonomous underwater vehicle
… the adverse pressure gradient, resulting in free vortex sheets which roll up to form a pair of body vortices. An adaptive mesh strategy is required to ensure a suitable mesh structure and density to capture these flow features. Modifications to a vortex capture algorithm (VORTFIND) are proposed, …
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Installed jet noise
… an analytical stability analysis for lobed vortex sheets is performed. The results show that lobed jets change both the convection velocity and the temporal growth rate of instability waves. The changes become more pronounced as the number of lobes $N$ and the penetration ratio $\epsilon$ …
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Numerical Investigation of the Wake of a Rectangular Wing
Wakes of lifting bodies contain vortex sheets that roll up into strong streamwise vortices. The long time behavior of such vortices depends on the turbulence in the wake and the stability characteristics of the vortices themselves. In the near wake of a rectangular wing the flow field consists of a …
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Fully nonlinear interfacial waves in a bounded two-fluid system
… numerical studies of unbounded three-dimensional vortex sheets (see Introduction for a discussion and references). In the final part of this work we consider the vortex-sheet formulation of the exact nonlinear two-dimensional flow of a vortex sheet which is bounded in a channel. We derive a …
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The effect of turboprop propulsion on the aerodynamic benefits of formation flight
… aerodynamic benefits of formation flight, a 3D Vortex Filament Method (VFM) programme, which made use of a Burnham-Hallock viscous core model, was formulated and employed to model the progression and interaction of the wing and turboprop trailing wakes. Within this programme, an initial …
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Unsteady Flow and Force Development in the case of a Circular Cylinder
… that whilst the potential flow `added mass' vortex sheet distribution around a stationary object immersed in an accelerating freestream is correct in shape, it ascribes the vortex sheet to the wrong origin. Instead, the vortex sheet is found to develop as a result of external vorticity that …