Mathematicians call the shape of a doughnut a 'toroid'. Physicists call a swirling fluid a 'vortex'. A toroidal vortex, then, is a swirling doughnut of fluid. This video from the Sleek Geeks archive ...

An artistic pressions of a vortex-ring street analogue to the structure of magnetic field of a NDSTP, where the right- and left- handed vortex rings were highlighted by blue and red, respectively. The ...

The knot theory originates in Lord Kevin's model proposed in 1867 that atoms are made of vortex rings or knots. Although the hypothesis was proved to be unsuccessful, the knot theory has since then ...

Here you see the good folks on QI shooting smoke rings across the room. Why does a donut-shaped cloud come out of a circular opening? Why are smokers able to blow smoke rings, even when they’re not ...

Humans do it with smoke. With a little snort, dolphins can produce a nearly perfect "air" rings, (sophisticated non-dolphins called them toroidal vortices) which they turn into underwater toys. If ...

The basic configuration of traditional propellers has not fundamentally changed since the first powered flight by the Wright brothers in 1903. However, as engineers learn more about aerodynamics and ...