The study of vortex-ring-induced stratified mixing has long played a key role in understanding externally-forced, stratified turbulent mixing. While several studies have investigated the dynamical evolution of a such a stratified system, this paper presents an experimental investigation of the three-dimensional mechanical evolution of these vortex rings with the specific goal of a understanding...

We follow the time evolution of a superfluid Fermi gas of resonantly interacting ^{6}Li atoms after a phase imprint. Via tomographic imaging, we observe the formation of a planar dark soliton, its subsequent snaking, and its decay into a vortex ring, which, in turn, breaks to finally leave behind a single solitonic vortex. In intermediate stages, we find evidence for an exotic structure resembl...

The influence of vortex ring state (VRS) on rotorcraft flight dynamics is investigated, specifically the vertical velocity drop of helicopters and the roll-off of tiltrotors encountering VRS. The available wind tunnel and flight test data for rotors in vortex ring state are reviewed. Test data for axial flow, nonaxial flow, two rotors, unsteadiness, and vortex ring state boundaries are describe...

A pattern often found in regions of recirculating flow is the vortex ring. Smoke rings and vortex breakdown bubbles are two familiar instances of this pattern. A vortex ring requires at least two critical points, and in fact this minimum number is observed in many synthetic or real-world examples. Based on this observation, we propose a visualization technique utilizing a Poincaré section that ...

A Lagrangian describing a gas of ideal pointlike vortices interacting with a quantum gas of spin-0 particles confined in an infinite or finite subset of R2 is derived. Singleand two-vortex dynamics is studied in the special case of a homogeneous gas in infinite and finite systems. Special attention is given to the case of the annulus (ring) for which new analytic and numerical solutions are fou...

Normal left ventricular (LV) filling occurs rapidly early in diastole caused by a progressive pressure gradient within the ventricle and with a low left atrial pressure. This normal diastolic function is altered in patients with heart failure. Such impairment of diastolic filling is manifested as an abrupt deceleration of the early filling wave velocity. Although variations within the early fil...

The "perfect" vortex is a new class of optical vortex beam having ring radius independent of its topological charge (order). One of the simplest techniques to generate such beams is the Fourier transformation of the Bessel-Gauss beams. The variation in ring radius of such vortices require Fourier lenses of different focal lengths and or complicated imaging setup. Here we report a novel experime...

Point vortex and vortex blob computations are used to investigate the evolution of the planar and the axisymmetric vortex sheet which initially induce ow past a cylinder and past a sphere respectively. In both cases the sheet develops a singularity at two points in the symmetry plane at a nite time. It rolls up at these points forming a vortex pair in the planar case and a vortex ring in the ax...

Denis Blackmore Department of Mathematical Sciences and Center for Applied Mathematics and Statistics New Jersey Institute of Technology Newark, NJ 07102-1982 [email protected] ∗ ∗ ∗ Morten Brøns Department of Mathematics Technical University of Denmark DK-2800 Kgs. Lyngby, Denmark [email protected] ∗ ∗ ∗ Arnaud Goullet Department of Mathematical Sciences New Jersey Institute of Technology New...

Left ventricular (LV) diastolic filling is characterized by the formation of intraventricular rotational bodies of fluid (termed "vortex rings") that optimize the efficiency of LV ejection. The aim of the present study was to evaluate the morphology and dynamics of LV diastolic vortex ring formation early after acute myocardial infarction (AMI), in relation to LV diastolic function and infarct ...