The present work considers the two-dimensional barotropic evolution of thin annular rings of enhanced vorticity embedded in nearly irrotational flow. Such initial conditions imitate the observed flows in intensifying hurricanes. Using a pseudospectral numerical model, it is found that these highly unstable annuli rapidly break down into a number of mesovortices. The mesovortices undergo merger ...

Typically a magnetohydrodynamical model for neutral plasmas must take into account both the ionic and the electron fluids and their interaction. However, at short time scales, the ionic fluid appears to be stationary compared to the electron fluid. On these scales, we need consider only the electron motion and associated field dynamics, and a single fluid model called the electron magnetohydrod...

We have reached our goal of implementing a computationally cheap algorithm for realtime rendering of realistic two-dimensional fire. The fire is simulated using computational fluid dynamics, vorticity confinement, and combustion modelling and visualized using black-body radiation. Small rotationally homogenous fires like torches and candles viewed in front are the best candidates when using thi...

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...

We study, experimentally, the dynamics of a binary mixture air-fluidized disks. The disks are chiral since they incorporate set blades with constant tilt. Both species identical except for their tilt angle, which is rotated by 180o in second species. analyze phase behavior system. Our analysis reveals wide range different fluid dynamics, including flow. This flow features its base state large v...

A new family of exact solutions is analysed, which models two-dimensional circulations of an ideal fluid in a uniformly rotating elliptical tank, under the semi-geostrophic approximation from meteorology and oceanography. The fluid pressure and stream function remain quadratic functions of space at each instant in time, and their fluctuations are described by a single degree of freedom Hamilton...

Synoptic-scalemonsoon disturbances produce themajority of continental rainfall in themonsoon regions of South Asia and Australia, yet there is little understanding of the conditions that foster development of these low pressure systems. Here a genesis index is used to associate monsoon disturbance genesis in a global domain with monthly mean, climatological environmental variables. This monsoon...

One of the important properties of boundary layer is, from the point of view of Strömungslehre, that it pumps vorticity into the flow field. Vorticity in fluid flows plays diverse roles and produces tremendous variety of flow phenomena. We consider four aspects of vorticity in fluid flows: (A) Kinematical aspect of a vortex sheet, (B) mechanical aspect of hydrodynamic impulse of a vortex system...

We consider solutions to the two-dimensional incompressible Euler system with only integrable vorticity, thus with possibly locally infinite energy. With such regularity, we use the recently developed theory of Lagrangian flows associated to vector fields with gradient given by a singular integral in order to define Lagrangian solutions, for which the vorticity is transported by the flow. We pr...

Bio-inspired mechanics of locomotion generally consist of the interaction of flexible structures with the surrounding fluid to generate propulsive forces. In this work, we extend, for the first time, the viscous vortex particle method (VVPM) to continuously deforming two-dimensional bodies. The VVPM is a high-fidelity Navier–Stokes computational method that captures the fluid motion through evo...