A water jacket is a water-filled casing surrounding a device, typically a metal sheath having intake and outlet vents to allow water to be pumped through and circulated. The flow of water to an external heating or cooling device allows precise

temperature control Temperature control is a process in which change of temperature of a space (and objects collectively there within), or of a substance, is measured or otherwise detected, and the passage of heat energy into or out of the space or substance is ad ...

of the device.

Applications

Water jackets are often used in watercooling. They are also used in

laboratory glassware Laboratory glassware refers to a variety of equipment used in scientific work, and traditionally made of glass. Glass can be blown, bent, cut, molded, and formed into many sizes and shapes, and is therefore common in chemistry, biology, and anal ...

Liebig Justus Freiherr von Liebig (12 May 1803 – 20 April 1873) was a German scientist who made major contributions to agricultural and biological chemistry, and is considered one of the principal founders of organic chemistry. As a professor at t ...

Graham Graham and Graeme may refer to: People * Graham (given name), an English-language given name * Graham (surname), an English-language surname * Graeme (surname), an English-language surname * Graham (musician) (born 1979), Burmese singer * Clan ...

, and Allihn condensers. Water jackets were used to cool the barrels of

machine gun A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifles ...

s until several years after the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

, but modern machine guns are air-cooled to conserve weight and hence increase portability. In a reciprocating piston

internal combustion engine An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal co ...

the water jacket is a series of holes either cast or bored through the main

engine block In an internal combustion engine, the engine block is the structure which contains the cylinders and other components. In an early automotive engine, the engine block consisted of just the cylinder block, to which a separate crankcase was attac ...

and connected by inlet and outlet valves to a

radiator Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in cars, buildings, and electronics. A radiator is always ...

. Equipment such as

tissue culture Tissue culture is the growth of tissues or cells in an artificial medium separate from the parent organism. This technique is also called micropropagation. This is typically facilitated via use of a liquid, semi-solid, or solid growth medium, su ...

incubators may be enclosed in a water jacket kept at a constant temperature.CO₂ Incubator: A Laboratory Staple

References

Cooling technology {{tech-stub