The confining mechanisms of 't Hooft and Mandelstam have a simple microscopic realization in 3D Z 2 gauge theory: the center vortex and the magnetic monopole condensation are associated, in the set of configurations contributing to the confining phase, to the presence of two kinds of infinite clusters. These generate the area law of the large Wilson loops and the universal finite size effects p...

Three-dimensional vortex-method simulations are made of a round jet forced by axisymmet-ric, helical and multiple disturbances. The multiple disturbances are combinations of two helical modes rotating in the opposite direction. The present simulations demonstrate the evolution of large-scale vortex structures in the forced jet. Results of the simulations are in reasonable agreement with availab...

We have observed phase singularities due to vortex excitation in Bose-Einstein condensates. Vortices were created by moving a laser beam through a condensate. They were observed as dislocations in the interference fringes formed by the stirred condensate and a second unperturbed condensate. The velocity dependence for vortex excitation and the time scale for re-establishing a uniform phase acro...

this paper is about experimental results for partial reduction of vortex at vertical pipe intakes. one of the easiest and practical ways of reducing vortex effect is to use anti-vortex plates or baffles. these plates can be used to avoid the vortex completely or partially. this paper will concentrate on the latter case. rectangular plates with different dimensions have been placed at different ...

The spreading and diffusion of two-dimensional vortices subject to weak external random strain fields is examined. The response to such a field of given angular frequency depends on the profile of the vortex and can be calculated numerically. An effective diffusivity can be determined as a function of radius and may be used to evolve the profile over a long time scale, using a diffusion equatio...