US Special Forces soldier fires a Carl Gustav rocket during a training exercise conducted in Basrah Iraq

A smoke ring is a visible

vortex ring A vortex ring, also called a toroidal vortex, is a torus-shaped vortex in a fluid; that is, a region where the fluid mostly spins around an imaginary axis line that forms a closed loop. The dominant flow in a vortex ring is said to be toroidal, ...

formed by

smoke Smoke is an aerosol (a suspension of airborne particulates and gases) emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwante ...

in a clear atmosphere. Smokers may blow smoke rings from the mouth, intentionally or accidentally. Smoke rings may also be formed by sudden bursts of

fire Fire is the rapid oxidation of a fuel in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products. Flames, the most visible portion of the fire, are produced in the combustion re ...

(such as lighting and immediately putting out a cigarette lighter), by shaking a smoke source (such as an incense stick) up and down, by firing certain types of

artillery Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...

, or by the use of special devices, such as vortex ring guns and vortex ring toys. The head of a

mushroom cloud A mushroom cloud is a distinctive mushroom-shaped flammagenitus cloud of debris, smoke, and usually condensed water vapour resulting from a large explosion. The effect is most commonly associated with a nuclear explosion, but any sufficiently e ...

is a large smoke ring. A smoke ring is commonly formed when a puff of smoke is suddenly injected into clear air, especially through a narrow opening. The outer parts of the puff are slowed by the still air (or by edges of the opening) relative to the central part, imparting it the characteristic poloidal flow pattern. The smoke makes the ring visible, but does not significantly affect the flow. The same phenomenon occurs with any fluid, producing vortex rings which are invisible but otherwise entirely similar to smoke rings. Rare visible vortex rings produced by volcanoes have been incorrectly called "smoke rings", despite being formed by the

condensation Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor ...

of erupting steam, rather than by

combustion Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion ...

Smoking and breathing

A smoker may produce rings by taking smoke into their mouth and expelling it with a tongue flick, by closing the jaw, tapping the cheek, or producing a sudden burst of air with the lungs and throat. The smoker may also use any of those methods to blow into a cloud of smoke outside their mouth. A trick often performed in conjunction with mouth-blown smoke rings is the French inhale. It is also possible to produce a vapour ring by using the same techniques on a cold day by exhaling. The most famous such steam rings were those produced during the mid-20th century by Douglas Leigh's billboard on the Hotel Claridge in New York City's

Times Square Times Square is a major commercial intersection, tourist destination, entertainment hub, and Neighborhoods in New York City, neighborhood in the Midtown Manhattan section of New York City. It is formed by the junction of Broadway (Manhattan), ...

, advertising Camel cigarettes. An automated steam chamber behind the billboard produced puffs of steam every four seconds, giving the appearance of smoke rings leaving the smoker's open mouth and drifting away. Inspired by a

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

-era prohibition on lighted advertising, the Camel smoker remained a Times Square landmark long afterwards. Some users of

electronic cigarette An electronic cigarette (e-cigarette), or vape, is a device that simulates smoking. It consists of an atomizer, a power source such as a battery, and a container such as a cartridge or tank. Instead of smoke, the user inhales vapor. As such ...

s modify their devices to inhale large amounts of vapour at once, to exhale "clouds" in patterns like smoke rings.

References

External links

*
How to puff a smoke ring?

Blowing a smoke ring
(

wikiHow wikiHow is an online wiki-style publication featuring informational articles and quizzes on a variety of topics. Founded in 2005 by Internet entrepreneur Jack Herrick, its aim is to create an extensive database of instructional content, using ...

)
Vortex rings generated by eruptions of Etna volcano

(see images on bottom) * Thomson, Sir William (Lord Kelvin),

', Proceedings of the Royal Society of Edinburgh, Vol. VI, 1867, pp. 94–105. * Silliman, Robert H., ''William Thomson: Smoke Rings and Nineteenth-Century Atomism'', Isis, Vol. 54, No. 4. (Dec., 1963), pp. 461–474
JSTOR link

Movie
of a modern recreation of Tait's smoke ring experiment
How to Blow Smoke Rings - Howiw

How To Blow Smoke Rings
{{DEFAULTSORT:Smoke Ring Vortices Smoke Smoking

Smoking and breathing

See also

References

External links