We consider the viscous motion of a thin, axisymmetric column of fluid with a free surface. A one-dimensional equation of motion for the velocity and the radius is derived from the Navier-Stokes equation. We compare with recent experiments on the breakup of a liquid jet and on the bifurcation of a drop suspended from an orifice. The equations form singularities as the fluid neck is pinching off...

The flow over two three-dimensional bluff bodies in tandem arrangement is widely encountered both natural environments and engineering applications. Here we perform a detailed numerical investigation on the wake bifurcations behind axisymmetric tandem. Our study explores overall range of Re between 100 - 500 separation distance $S/d$=1, 2, 4, 6. Seven main regimes are identified, bifurcation sc...

The rotational motion of an interacting Bose-Einstein condensate confined by a harmonic trap is investigated by solving the hydrodynamic equations of superfluids, with the irrotationality constraint for the velocity field. We point out the occurrence of an overcritical branch where the system can rotate with angular velocity larger than the oscillator frequencies. We show that in the case of is...

We investigate the phenomenon of irregular bifurcations in axisymmetric scalefree potentials, in which a tube orbit gives rise to a new family of orbits of period 3. A proper understanding of the formation of this irregular family of orbits is important because the family occupies a fair portion of the phase space in models where it occurs. We show that these bifurcations are related to the tra...

A study of the effect of an externally imposed magnetic field on the axisymmetry-breaking instability of an axisymmetric convective flow, associated with crystal growth from bulk of melt, is presented. Convection in a vertical cylinder with a parabolic temperature profile on the sidewall is considered as a representative model. A parametric study of the dependence of the critical Grashof number...

Plasma balls and rings emerge as fluid holographic duals of black holes and black rings in the hydrodynamic/gravity correspondence for the Sherck-Schwarz AdS system. Recently, plasma balls spinning above a critical rotation were found to be unstable against m-lobed perturbations. In the phase diagram of stationary solutions the threshold of the instability signals a bifurcation to a new phase o...

We report the first direct measurement of the internal magnetic field structure associated with a 3D helical equilibrium generated spontaneously in the core of an axisymmetric toroidal plasma containment device. Magnetohydrodynamic equilibrium bifurcation occurs in a reversed-field pinch when the innermost resonant magnetic perturbation grows to a large amplitude, reaching up to 8% of the mean ...

Plumes due to localized buoyancy sources are of wide interest owing to their prevalence in many situations. This study investigates the transition from laminar to turbulent dynamics. Several experiments have reported that this transition is sensitive to external perturbations. As such, a well-controlled set-up has been chosen for our numerical study, consisting of a localized heat source at the...

We investigate critical points of the Onsager free-energy model on a sphere with different potential kernels, including dipolar potential, Maier-Saupe coupled dipolar/Maier-Saupe and potential. A uniform sampling method is implemented for discretization model, solution landscapes are constructed using saddle dynamics downward/upward search algorithms. first construct potentials, which all axisy...