Recent results are presented from the application of a grid-free vortex method to the prediction of turbulent aerodynamic flows produced by road vehicles. The approach has the character of a large eddy simulation and incorporates a fast technique for evaluating the mutual interactions of several million vortex elements needed in describing the dynamically significant structure of the turbulent ...

A coherent-vortex analysis is made of a computational solution for the free decay of homogeneous, Charney-isotropic geostrophic turbulence at large Reynolds number. The method of analysis is a vortex detection and measurement algorithm that we call a vortex census. The census demonstrates how, through non-conservative interactions among closely approaching vortices, the vortex population evolve...

A Lagrangian numerical method based on impulse variables is analyzed. The relation between impulse vectors and vortex dipoles with a prescribed dipole moment is presented and used to adapt the high-accuracy cutoo functions of vortex methods for use in impulse-based methods. The long-time implementation of the impulse method is shown to contain a source of error whose growth in time renders impu...

We present a numerical method for generating vortex rings in BoseEinstein condensates confined in axially symmetric traps. The vortex ring is generated using the line-source approximation for the vorticity, i.e., the rotational of the superfluid velocity field is different from zero only on a circumference of given radius located on a plane perpendicular to the symmetry axis and coaxial with it...

The zero temperature vortex phase diagram for uniaxial anisotropic superconductors placed in an external magnetic field tilted with respect to the axis of anisotropy is studied for parameters typical of BSCCO and YBCO. The exact Gibbs free energy in the London approximation, using a self-energy expression with an anisotropic core cutoff, is minimized numerically, assuming only that the equilibr...

The method of contour dynamics, developed for two-dimensional vortex patches by Zabusky, Hughes, and Roberts [34] is extended to vortex rings in which the vorticity distribution varies linearly with normal distance from the symmetry axis. The method tracks the motion of the boundaries of the vorticity regions and hence reduces the dimensionality of the problem by one. We discuss the formulation...

The Match method for the quantification of polar chemical ozone loss is investigated mainly with respect to the impact of the transport of air masses across the vortex edge. For the winter 2002/03, we show that significant transport across the vortex edge occurred and was simulated by the Chemical Lagrangian Model of the Stratosphere. In-situ observations of inert tracers and ozone from HAGAR o...

This report represents an overview of the interconnections between the dynamics of large vortex systems, combinatorics, n-body problems and statistical mechanics. The combinatorial perturbation method for the 2D vortex problem is discussed; the essential combinatorial sym-plectic transformations to Jacobi-type variables which are based on a binary tree algorithm, is introduced and extended to t...

The experimental investigation of superfluid turbulence in 3 He-B is generally not possible with the techniques which have been developed for 4 He-II. We describe a new method by which a transient burst of turbulent vortex expansion can be generated in 3 He-B. It is based on the injection of a few vortex loops into rotating vortex-free flow. The time-dependent evolution of the quantized vortici...

In this work, a penalization method is discussed in the context of vortex methods for incompressible flows around complex geometries. In particular, we illustrate the method in two cases: the flow around a rotating blade for Reynolds numbers 1000 and 10,000 and the flow past a semi-circular body consisting of a porous layer surrounding a rigid body at Reynolds numbers 550 and 3000. In the latte...