The XY model with quenched random disorder is studied numerically at T 1⁄4 0 by a defect scaling method as a model of a disordered superconductor. In 3D we find that, in the absence of screening, a vortex glass phase exists at low T for large disorder in 3D with stiffness exponent h þ0:31 and with finite screening and in 2D this phase does not exist. For weak disorder, a superconducting phase e...

When a vortex beam with a spiral phase structure passes through dynamic angular double slits (ADS), the interference pattern changes alternatively between destructive and constructive at the angular bisector of the ADS. This change is due to their phase difference. Based on this property, we experimentally demonstrate a simple method to precisely and efficiently determine the topological charge...

A new method for directly assimilating Lagrangian tracer observations for flow state estimation is presented. It is developed in the context of point vortex systems. With tracer advection equations augmenting the point vortex model, the correlations between the vortex and tracer positions allow one to use the observed tracer positions to update the non-observed vortex positions. The method work...

We study the growth of disturbances to vortex rings with swirl, which are exact solutions of the Euler equations of inviscid ow, using two contrasting methods. The motion of the perturbed vortex rings can be regarded as a prototype for the inviscid dynamics of vortex structures in 3D. Exact rings with swirl are computed as steady, axisymmetric ows using a variational method. Asymptotic analysis...

In this investigation we propose a computational approach for solution of optimal control problems for vortex systems with compactly supported vorticity. The problem is formulated as PDE–constrained optimization in which the solutions are found using a gradient–based descent method. Recognizing such Euler flows as free– boundary problems, the proposed approach relies on shape differentiation co...

This paper aims to apply two methods namely, Vortex Method and Higher Order Spectral Method to study the wave breaking and wave interaction. The breaking of shallow water gravity wave is performed using Vortex method, while the interaction between two gravity waves is carried out using Higher Order Spectral (HOS) method. In Vortex method an interface defined by a density or velocity discontinui...

this paper presents a k- turbulence model for simulation of steady current and itsinduced vortex shedding caused by the presence of an offshore pipeline. performance of the modelaround a circular cylinder above a wall with gap to diameter ratios of 0.1, 0.35 and 0.5 underdifferent flow regimes with reynolds numbers of 1500, 2500 and 7000 is studied. the flow field iscomputed with solving the re...

in this paper the effect of block shape vortex generators (vgs) on an air-water fin-tube heat exchanger has been studied experimentally using exergy analysis method. also the effect of these vgs on increasing heat transfer rate has been simulated numerically and the results show a good agreement with the experiments. in this research we used a wind tunnel to produce wind flow over heat exchange...

The dynamics of vortex flow is studied theoretically and numerically. Starting from a local analysis, where the perturbation in the vortex flow is Fourier decomposed in both radial and azimuthal directions, a modified Chebyshev polynomial method is used to discretize the linearized governing operator. The spectrum of the operator is divided into three groups: discrete spectrum, free-stream spec...

BACKGROUND LV diastolic vortex formation has been suggested to critically contribute to efficient blood pumping function, while altered vortex formation has been associated with LV pathologies. Therefore, quantitative characterization of vortex flow might provide a novel objective tool for evaluating LV function. The objectives of this study were 1) assess feasibility of vortex flow analysis du...