Vortex - Further Examples

Further Examples

• In the hydrodynamic interpretation of the behaviour of electromagnetic fields, the acceleration of electric fluid in a particular direction creates a positive vortex of magnetic fluid. This in turn creates around itself a corresponding negative vortex of electric fluid. Exact solutions to classical nonlinear magnetic equations include the Landau-Lifshitz equation, the continuum Heisenberg model, the Ishimori equation, and the nonlinear Schrödinger equation.
• Bubble rings are underwater vortex rings whose core traps a ring of bubbles, or a single donut-shaped bubble. They are sometimes created by playful dolphins and whales.
• The lifting force of aircraft wings, propeller blades, sails, and other airfoils can be explained by the creation of a vortex superimposed on the flow of air past the wing.
• Aerodynamic drag can be explained in large part by the formation of vortices in the surrounding fluid that carry away energy from the moving body.
• Large whirlpools can be produced by ocean tides in certain straits or bays. Examples are Charybdis of classical mythology in the Straits of Messina, Italy; the Naruto whirlpools of Nankaido, Japan; the Maelstrom at Lofoten, Norway.
• Vortices in the Earth's atmosphere are important phenomena for meteorology. They including mesocyclones on the scale of a few miles, tornados, waterspouts, and hurricanes. These vortices are often driven by temperature and humidity variations with altitude. The sense of rotation of hurricanes is influenced by the Earth's rotation. Another example is the Polar vortex, a persistent, large-scale cyclone centered near the Earth's poles, in the middle and upper troposphere and the stratosphere.
• Vortices are prominent features of the atmospheres of other planets. They include the permanent Great Red Spot on Jupiter and the intermittent Great Dark Spot on Neptune, as well as the Martian dust devils and the North Polar Hexagon of Saturn.
• Sunspots are dark regions on the Sun's visible surface (photosphere) marked by a lower temperature than its surroundings, and intense magnetic activity.
• The accretion disks of black holes and other massive gravitational sources.