We study vortex pattern formation in thin ferromagnetic films under the action of strong spin-polarized currents. Considering the currents which are polarized along the normal of the film plane, we determine the critical current above which the film goes to a saturated state with all magnetic moments being perpendicular to the film plane. We show that stable square vortex-antivortex superlattic...

Two-dimensional vortex pairs are frequently observed in geophysical conditions, for example, in a shelf zone of the ocean near river mouths. The main aims of the work are to estimate the space scales of such vortex structures, to analyze possible scenarios of vortex pair motion and to give the qualitative classification of their trajectories. We discuss some features of the motion of strong loc...

The interaction between vortex density waves and high-frequency second sound in counterflow superfluid turbulence is examined, incorporating diffusive and elastic contributions of the vortex tangle. The analysis is based on a set of evolution equations for the energy density, the heat flux, the vortex line density, and the vortex flux, the latter being considered here as an independent variable...

Results of a numerical simulation are presented to determine the feasibility of estimating the location and strength of a wake vortex from imperfect in-situ measurements. These estimates could be used to provide information to a pilot on how to avoid a hazardous wake vortex encounter. An iterative algorithm based on the method of secants was used to solve the four simultaneous equations describ...

– Linear diamagnetism is predicted in the vortex-liquid phase of layered superconductors at temperatures just below the mean-field phase transition on the basis of a hightemperature analysis of the corresponding frustrated XY model. The diamagnetic susceptibility, and the Nernst signal by implication, is found to vanish with temperature as (Tc0 − T ) 3 in the vicinity of the meanfield transitio...

It is of interest to determine the exit angle of a vortex from a superconductor surface, since this affects the intervortex interactions and their consequences. Two ways to determine this angle are to image the vortex magnetic fields above the surface, or the vortex core shape at the surface. In this work we evaluate the field h(x,y,z) above a flat superconducting surface x,y and the currents J...

1 Modeling bubble-vortex interactions Simulations of bubble entrainment and interactions with two dimensional vorti-cal flows are preformed using a Discrete Element Model (DEM). In this Eulerian-Lagrangian approach, solution to the carrier phase is obtained using direct numerical simulation whereas motion of subgrid bubbles is modeled using Lagrangian tracking. The volumetric displacement of th...

Starting flow through a nozzle or orifice typically results in the transient formation of a leading vortex ring and trailing jet. Experiments are conducted to investigate the dynamics of this process in the case of a temporally variable nozzle exit diameter, with the aim of understanding these flows as they occur in Nature and emerging technologies. By kinematically decoupling the source flow f...

This paper is an attempt to attain a new and profound model of the nature’s structure using a vortex-fractal theory (VFT). Scientists try to explain some phenomena in Nature that have not been explained so far. The aim of this paper is the vortex-fractal modeling of vortex-ring fractal structure of atoms, molecules, and a creation of elements in the Mendeleev’s periodic table with vortex-ring p...

In the present study, turbulent flow visualization is carried out to understand the vortex formation mechanism behind a trapezoidal bluff body, for vortex flowmeter application. The dye used for flow v isualization is shearthickening and h igh extension viscosity fluid, which can sustain turbulent separated flows. W ith the quantitative assessment of the images, the vortex frequency is computed...