SUNDAY, SEPTEMBER 25, 2011
Toroidal Vortices is the plural of Toroidal Vortex, or more simply, a ‘vortex ring’. It’s an area of rotating substance that moves through the same or different substance, where the flow pattern takes on a doughnut-like – or toroidal – shape. A good example is a smoke ring, as amply demonstrated below by silver screen legend, Jack Nicholson.
Jack has had some recent competition in the smoke ring department by good old Mother Nature when Mount Etna stirred this summer to produce a giant version, a rare occurrence which had previously only been documented in 1970 and 2000.
However, MB&F’s attention has been caught not so much by the smoke-air version of toroidal vortices, as by the air-liquid ones.
Of course, if they try hard enough, humans can make some artistically aquatic patterns when scuba diving. Yet when it comes to making water-based circular air bubbles, it’s dolphins who have really got this trick down to a fine art.
Dolphins are well known for their echolation – their biological sonar – as a way of communicating. But these supremely social animals also communicate through playfully creating toroidal vortices, by either blowing a near-perfect ring out of their blowhole or by flipping a dorsal fin quick enough to make a water vortex.
Vortex rings are believed to be part of the sonic tool-kit of dolphins and other cetaceans – aquatic mammals such as whales and porpoises. They can play with these rings by bouncing them off walls, stretching them with their flippers into large, long spirals, and by swimming through them before breaking them up into little bubbles.
The ring of air as well as the nearby water spins “poloidally” as it travels through the water, like a flexible bracelet might spin when it is rolled onto a person’s arm. The faster the bubble ring spins, the more stable it becomes.
Vortex rings were first mathematically analysed in 1867 by the German physicist Hermann von Helmholtz in his paper On Integrals of the Hydrodynamical Equations which Express Vortex-motion.
But that's enough reading, time to sit back and relax watching this compilation of toroidal vortices including dophins playing and one the most powerful nuclear weapon ever detonated, the Tsar Bomba, tested by the Soviets in 1961.
Lords of the Rings - Toroidal Vortices
Have you ever heard of Toroidal Vortices? No? Well neither had we until recently. Don’t worry, it’s not a tropical disease that you should see your doctor about. Neither is it Real Madrid’s new South American striker. Nor is it the name of some obscure 1970s prog rock band.Toroidal Vortices is the plural of Toroidal Vortex, or more simply, a ‘vortex ring’. It’s an area of rotating substance that moves through the same or different substance, where the flow pattern takes on a doughnut-like – or toroidal – shape. A good example is a smoke ring, as amply demonstrated below by silver screen legend, Jack Nicholson.
Jack has had some recent competition in the smoke ring department by good old Mother Nature when Mount Etna stirred this summer to produce a giant version, a rare occurrence which had previously only been documented in 1970 and 2000.
However, MB&F’s attention has been caught not so much by the smoke-air version of toroidal vortices, as by the air-liquid ones.
Of course, if they try hard enough, humans can make some artistically aquatic patterns when scuba diving. Yet when it comes to making water-based circular air bubbles, it’s dolphins who have really got this trick down to a fine art.
Dolphins are well known for their echolation – their biological sonar – as a way of communicating. But these supremely social animals also communicate through playfully creating toroidal vortices, by either blowing a near-perfect ring out of their blowhole or by flipping a dorsal fin quick enough to make a water vortex.
Vortex rings are believed to be part of the sonic tool-kit of dolphins and other cetaceans – aquatic mammals such as whales and porpoises. They can play with these rings by bouncing them off walls, stretching them with their flippers into large, long spirals, and by swimming through them before breaking them up into little bubbles.
The ring of air as well as the nearby water spins “poloidally” as it travels through the water, like a flexible bracelet might spin when it is rolled onto a person’s arm. The faster the bubble ring spins, the more stable it becomes.
Vortex rings were first mathematically analysed in 1867 by the German physicist Hermann von Helmholtz in his paper On Integrals of the Hydrodynamical Equations which Express Vortex-motion.
But that's enough reading, time to sit back and relax watching this compilation of toroidal vortices including dophins playing and one the most powerful nuclear weapon ever detonated, the Tsar Bomba, tested by the Soviets in 1961.
