Water injection is a method for cooling the combustion chambers of engines by adding water to the incoming fuel-air mixture, allowing for greater compression ratios and largely eliminating the problem of engine knocking. This effectively increases the octane rating of the fuel, meaning that performance gains can be obtained when used in conjunction with a supercharger or turbocharger, altered spark ignition timing, and other modifications. Many water injection systems use a mixture of water and alcohol (usually 50/50), partly because the alcohol is combustible, while water is not; in addition, the alcohol serves as an antifreeze for the water. Hence, water injection is also often known as methanol-water injection, owing to the fact that the alcohol mixed into the injection solution is often methanol, CH₃OH. A combustion chamber is part of an engine in which fuel is burned. ... For other uses, see Engine (disambiguation). ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... For other uses, see Fuel (disambiguation). ... Look up air in Wiktionary, the free dictionary. ... Bold text The compression ratio is a single number that can be used to predict the performance of any engine (such as an internal-combustion engine or a Stirling Engine). ... Knocking (also called pinking or pinging)— colloquially detonation—in internal combustion engines occurs when air/fuel mixture in the cylinder detonates or ignites prior to the timed pre-set conditions in the engines cylinder(s). ... A gas station pump offering five different octane ratings. ... A supercharger (also known as a blower) is an air compressor used to force more air (and hence more oxygen) into the combustion chamber(s) of an internal combustion engine than can be achieved at ambient atmospheric pressure (natural aspiration). ... Air foil bearing-supported turbocharger cutaway made by Mohawk Innovative Technology Inc. ... This article or section should include material from Spark gap A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed aerosol gasoline by means of an electric spark. ... This article does not cite any references or sources. ... Antifreeze is used in internal combustion engines, and for many other heat transfer applications, such as electronics cooling and chillers for HVAC. Compounds are added to water to reduce the freezing point of the mixture to below the lowest temperature that the system is likely to be exposed to, and... Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naptha or wood spirits, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). ...

Due to its corrosive nature, the alcohol in water injection systems cannot be ethanol. Only methanol and isopropanol are used, methanol being the more commonly-utilised form of alcohol for this purpose due to its higher availability and lower cost than isopropanol. Isopropyl alcohol or isopropanol is a common name for 2-propanol, an alcohol commonly used for application to the skin, and popularly referred to as rubbing alcohol. ...

Water injection is often necessary when adding forced induction to an engine that was not designed for it; the compression ratio of a normally-aspirated engine is too high to cope with more than a very modest boost unless this technique is used. Bold text The compression ratio is a single number that can be used to predict the performance of any engine (such as an internal-combustion engine or a Stirling Engine). ... Look up boost in Wiktionary, the free dictionary. ...

The system was first used extensively on World War II fighter aircraft to increase power upon takeoff and bring up the service ceiling. A limited number of road vehicles with large-displacement engines from manufacturers such as Chrysler have also included water injection. Saab offered water injection for the Saab 99 Turbo. With the introduction of the intercooler the interest in water injection disappeared, but today, water injection is also of interest because it can potentially decrease nitrogen oxide (NO_x) emissions in exhaust. Water injection is primarily used with piston-powered internal combustion engines, but it has also seen use with turbines. Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... An A-10 Thunderbolt II, F-86 Sabre, P-38 Lightning and P-51 Mustang fly in formation during an air show at Langley Air Force Base, Virginia. ... In aeronautics, the service ceiling is the maximum density altitude where the best rate of climb airspeed will produce a 100 feet per minute climb(twin engine) and 50 feet(single engine) at maximum weight while in a clean configuration with maximum continuous power. ... For other uses, including the Chrysler Brand, see Chrysler (disambiguation). ... For the manufacturer of Saab cars, see Saab Automobile. ... The 99 was an automobile produced by Saab from 1969 to 1984. ... An intercooler, or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged and supercharged internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through isochoric cooling. ... The term nitrogen oxide is a general term and can be used to refer to any of these oxides (oxygen compounds) of nitrogen, or to a mixture of them: Nitric oxide (NO), nitrogen(II) oxide Nitrogen dioxide (NO2) Dinitrogen monoxide (N2O) (Nitrous oxide) Dinitrogen trioxide (N2O3) Dinitrogen tetroxide (N2O4) Dinitrogen... Look up exhaust in Wiktionary, the free dictionary. ... For the American composer, see Walter Piston. ... The internal combustion engine is an engine in which the combustion of fuel and an oxidizer (typically air) occurs in a confined space called a combustion chamber. ... A Siemens steam turbine with the case opened. ...

The initial injection of water cools the fuel-air mixture somewhat, which increases its density and hence the amount of mixture that enters the cylinder. But the greater effect comes later during combustion when the water takes in significant amounts of heat energy as it converts from liquid to gas (steam), increasing piston pressure (torque) and reducing the peak temperature with its resultant NO_x formation as well as the amount of energy absorbed into the cylinder walls. The duration of combustion is said to be longer. An interesting side effect that has been reported by some is that water injection effectively "steam cleans" the engine interior, resulting in less carbon residue buildup. Glowing hot carbon deposits are a known cause of knocking. For other uses, see Liquid (disambiguation). ... Gas can also refer to gasoline and natural gas and also hydrogen. ... For other uses, see Steam (disambiguation). ... Torque applied via an adjustable end wrench Relationship between force, torque, and momentum vectors in a rotating system In physics, torque (or often called a moment) can informally be thought of as rotational force or angular force which causes a change in rotational motion. ... This article or section does not cite any references or sources. ...

Fuel economy can be improved with water injection, although the effect on most engines with no other modification, like leaning out the mixture, appears to be rather limited or even negligible in some cases. Fuel efficiency, sometimes also referred to as fuel economy and commonly gas mileage in the United States, is a numeric measure often used to describe the amount of fuel consumed with regard to the distance travelled in a transportation vehicle, such as an automobile. ...

Some degree of control over the water injection is important. It needs to be injected only when the engine is heavily loaded and the throttle is wide open; as with other systems which need to monitor engine load, this can be determined by manifold vacuum, which is low when the engine is loaded and high when it is unloaded; however, provision must be made for starting, when the manifold vacuum is also low but water injection is undesirable. Manifold vacuum, or engine vacuum in an internal combustion engine is the difference in air pressure between the engines intake manifold and Earths atmosphere. ...

Reports of more rapid corrosion of the steel and cast iron components of engines to which water injection has been added suggest that more frequent oil changes, particularly when the engine does not experience sustained high temperature operation to evaporate any water from the oil, are prudent. For the hazard, see corrosive. ... // A typical container of motor oil, with some in a glass. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Synthetic motor oil An oil is any substance that is in a viscous liquid state (oily) at ambient temperatures or slightly warmer, and is both hydrophobic (immiscible with water, literally water fearing) and lipophilic (miscible with other oils, literally fat loving). This general definition includes compound classes with otherwise unrelated...

See also the Crower six stroke engine developed by Bruce Crower with steam stroke. The Crower six-stroke engine or Crower Cycle is a concept under development by Bruce Crower. ...

References

NACA Wartime Memorandum Report E5H12 08/1945

• Water Vapor Injection Fueleconomytips.com

• Water injection forum MpgResearch.com

• Water Injection Wizardry. Mother Earth News, September/October 1979.

• 116+ Octane With Water Injection! The Power Of Water Injection

• Knock Knock. Who's There? Detonation! Understanding Detonation & How Water/Alcohol Injection Can Help Prevent It