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VORTEX

A vortex can be seen in the spiraling motion of air or liquid around a center of rotation. The circular current of water of conflicting tides often form vortex shapes. Turbulent flow makes many vortices. A good example of a vortex is the atmospheric phenomenon of a whirlwind or a tornado or dust devil. This whirling air mass mostly takes the form of a helix, column, or spiral. Tornadoes develop from severe thunderstorms, usually spawned from squall lines and supercell thunderstorms, though they sometimes happen as a result of a hurricane.
In atmospheric physics, a mesovortex is on the scale of a few miles (smaller than a hurricane but larger than a tornado). [2] On a much smaller scale, a vortex is usually formed as water goes down a drain, as in a sink or a toilet. This occurs in water as the revolving mass forms a whirlpool. This whirlpool is caused by water flowing out of a small opening in the bottom of a basin or reservoir. This swirling flow structure within a region of fluid flow opens downward from the water surface.

Quote is from Wikipedia


	This is an old fashioned Fun Fair game using coins to roll faster and faster into the funnel of the vortex shape and down the hole.
	Click on the image to see a movie showing how it works

Lifespan of a tornado?

Formation
As the mesocyclone approaches the ground, a visible condensation funnel appears to descend from the base of the storm, often from a rotating wall cloud. As the funnel descends, the RFD also reaches the ground, creating a gust front that can cause damage a good distance from the tornado. Usually, the funnel cloud becomes a tornado within minutes of the RFD reaching the ground.
Maturity
Initially, the tornado has a good source of warm, moist inflow to power it, so it grows until it reaches the "mature stage". This can last anywhere from a few minutes to more than an hour, and during that time a tornado often causes the most damage, and in rare cases can be more than one mile (1.6 km) across. Meanwhile, the RFD, now an area of cool surface winds, begins to wrap around the tornado, cutting off the inflow of warm air which feeds the tornado.

Demise
As the RFD completely wraps around and chokes off the tornado's air supply, the vortex begins to weaken, and become thin and rope-like. This is the "dissipating stage"; often lasting no more than a few minutes, after which the tornado fizzles. During this stage the shape of the tornado becomes highly influenced by the winds of the parent storm, and can be blown into fantastic patterns.
Even though the tornado is dissipating, it is still capable of causing damage. The storm is contracting into a rope-like tube and, like the ice skater who pulls her arms in to spin faster, winds can increase at this point.
As the tornado enters the dissipating stage, its associated mesocyclone often weakens as well, as the rear flank downdraft cuts off the inflow powering it. In particular, intense supercells tornadoes can develop cyclically. As the first mesocyclone and associated tornado dissipate, the storm's inflow may be concentrated into a new area closer to the center of the storm. If a new mesocyclone develops, the cycle may start again, producing one or more new tornadoes. Occasionally, the old (occluded) mesocyclone and the new mesocyclone produce a tornado at the same time.
Although this is a widely accepted theory for how most tornadoes form, live, and die, it does not explain the formation of smaller tornadoes, such as landspouts, long-lived tornadoes, or tornadoes with multiple vortices. These each have different mechanisms which influence their development—however, most tornadoes follow a pattern similar to this one.

Quote is from Wikipedia


	Supercell relationship. Tornadoes often develop from a class of thunderstorms known as supercells. Supercells contain mesocyclones, an area of organized rotation a few miles up in the atmosphere, usually 1–6 miles (2–10 km) across. Most intense tornadoes (EF3 to EF5 on the Enhanced Fujita Scale) develop from supercells. In addition to tornadoes, very heavy rain, frequent lightning, strong wind gusts, and hail are common in such storms. Most tornadoes from supercells follow a recognizable life cycle. That begins when increasing rainfall drags with it an area of quickly descending air known as the rear flank downdraft (RFD). This downdraft accelerates as it approaches the ground, and drags the supercell's rotating mesocyclone towards the ground with it.

	Spiral flame Vortex found while working on the AUDI R8 commercial. We discovered that we could make repeatable spiral shaped flames using a cylinder and a powerful flame.
	Click on the photo to view a workshop video

	Tornado demo machine This is a "tornado" made out of "cracked" water in a machine we bought in America. The machine is normally used for educational purposes and uses a small fan below, blowing into the six columns, (to cause a circular motion), and one fan above to cause an updraft.
	Click on the photo to view a workshop video


	Click on image to see the workshop movie

Big tornado demo machine

This machine is an enlarged copy of the machine above, made to test the possibilities of imitating a tornado using larger objects...

	Standing water vortex made for a commercial The vortex was continuous; the rate that the water ran out of the tank was the same as the rate at which the water was replenished, (see set photo below). There is a cylindrical perspex insert in the tank to enhance the spiral. The standing vortex does not have to reach the floor of the tank but can end halfway according to the rate of water flow.


	Click on image to see enlargement