Numerical experiments on vortex ring formation

Numerical experiments on vortex ring formation

Numerical simulations are used to study the formation of vortex rings that are generated by applying a non-conservative force of long duration, simulating experimental vortex ring generation with large stroke ratio. For sufficiently long-duration forces, we investigate the extent to which properties of the leading vortex ring are invariant to the force distribution. The results confirm the exis...

Assessing the role of oxygen on ring current formation and evolution through numerical experiments

Low O+/H+ ratio produced stronger ring currentInclusion of physics-based ionospheric outflow leads to a reduction in the CPCPOxygen presence is linked to a nightside reconnection point closer to the Earth.

Experiments on spontaneous vortex formation in Josephson tunnel junctions

A numerical study of vortex ring formation at the edge of a circular tube

An axisymmetric vortex-sheet model is applied to simulate an experiment of Didden (1979) in which a moving piston forces fluid from a circular tube, leading to the formation of a vortex ring. Comparison between simulation and experiment indicates that the model captures the basic features of the ring formation process. The computed results support the experimental finding that the ring trajecto...

Numerical Study on Mechanism of Multiple Ring Formation

In this paper, the mechanism of momentum deficit formation about the vortex legs is deeply studied. A new mechanism on how the multiple rings are formed one by one is presented. It is found that the momentum deficit is generated by vortex ring leg ejection. The momentum deficit forms shear layers above the vortex legs. The shear layers finally form new vortex rings one by one.