This work reports evidence for the existence of coherent structures in steady-state shear-flow driven plasmas in the Large Plasma Device W. Gekelman et al., Rev. Sci. Instrum. 62, 2875 1991 facility at UCLA. The measurements are performed with the vorticity probe VP , a probe that directly measures the plasma vorticity associated with the E B shear flow by means of a method that is both simpler...

Thom's vorticity condition for solving the incompressible Navier-Stokes equations is generally known as a rst-order method since the local truncation error for the value of boundary vorticity is rst order accurate. In the present paper, it is shown that convergence in the boundary vorticity is actually second order for steady problems and for time-dependent problems when t > 0. The result is pr...

Holographic PIV is used to measure the three-dimensional velocity distribution of fully developed turbulent flow within a square duct at ReH = 1.2 × 10. The data is used for mapping the structure of the filtered, three-dimensional vorticity, strain-rate and subgrid-scale (SGS) stress tensor distributions. Visualizations of iso-vorticity surfaces show structures that are only slightly elongated,...

Apparent interactions between ducted gravity waves and pre-existing mesocyclones are investigated. Preliminary analyses of WSR-88D radar observations from several cases reveal that the intersection of fine lines, whose propagation speed is consistent with that of gravity waves, and existing mesocyclones leads to an increase in rotational velocity of the mesocyclone. Utilizing simplified ducted ...

A novel vorticity based solution methodology has been developed to compute unsteady ow, particularly separation. The vorticity of the ow is determined on a set of points and the vorticity in the eld is computed by linear interpolation. This is accomplished by the construction of a connected set of triangular elements formed by Delaunay triangularization of the points in the eld. Triangulation o...

The classical Bondi-Hoyle formula gives the accretion rate onto a point particle of a gas with a uniform density and velocity. However, the Bondi-Hoyle problem considers only gas with no net vorticity, while in a real astrophysical situation accreting gas invariably has at least a small amount of vorticity. We therefore consider the related case of accretion of gas with constant vorticity, for ...

In this paper we investigate the use of divergence-free wavelet bases for the Coherent Vortex Extraction (CVE) of turbulent flows. We begin with a short presentation of the construction of 3D divergence-free biorthogonal wavelets. Then we apply the CVE decomposition to a homogeneous isotropic turbulent flow, computed by a direct numerical simulation at resolution 240 and upsampled to N = 256. A...

In previous investigations, the moving contact line has been reported as a significant source of vorticity. In the context of ship hydrodynamics, this subject is of significant interest as vorticity generated by the countless bubbles along a ship hull likely contribute to increased drag and wake signatures. In order to understand these phenomena better and potentially increase ship efficiency a...

Diastolic dysfunction, a leading cause of heart failure in the US, is a complex pathology which manifests morphological and hemodynamic changes in the heart and circulatory system. Recent advances in time-resolved phase-contrast cardiac magnetic resonance imaging (4D Flow) have allowed for characterization of blood flow in the right ventricle (RV) and right atrium (RA), including calculation of...

A Poisson regression between the observed climatology of tropical cyclogenesis (TCG) and largescale climate variables is used to construct a TCG index. The regression methodology is objective and provides a framework for the selection of the climate variables in the index. Broadly following earlier work, four climate variables appear in the index: low-level absolute vorticity, relative humidity...