Editing Engine (section)

== History ==
=== Antiquity ===
[[Simple machine]]s, such as the [[Mace (bludgeon)|club]] and [[oar]] (examples of the [[lever]]), are [[Prehistory|prehistoric]]. More complex engines using [[human power]], [[Working animals|animal power]], [[Water wheel|water power]], [[Windmill|wind power]] and even steam power date back to antiquity. Human power was focused by the use of simple engines, such as the [[Capstan (nautical)|capstan]], [[windlass]] or [[Treadwheel|treadmill]], and with [[rope]]s, [[pulley]]s, and [[block and tackle]] arrangements; this power was transmitted usually with the forces [[mechanical advantage|multiplied]] and the speed [[gear reduction|reduced]]. These were used in [[Crane (machine)|cranes]] and aboard [[ship]]s in [[Ancient Greece]], as well as in [[Mining|mines]], [[Pump|water pumps]] and [[siege engines]] in [[Ancient Rome]]. The writers of those times, including [[Vitruvius]], [[Frontinus]] and [[Pliny the Elder]], treat these engines as commonplace, so their invention may be more ancient. By the 1st century AD, [[cattle]] and [[horse]]s were used in [[Mill (grinding)|mills]], driving machines similar to those powered by humans in earlier times.

According to [[Strabo]], a water-powered mill was built in Kaberia of the [[Parthian Empire|kingdom of Mithridates]] during the 1st century BC. Use of [[water wheel]]s in mills spread throughout the [[Roman Empire]] over the next few centuries. Some were quite complex, with [[aqueduct (bridge)|aqueducts]], [[dam]]s, and [[sluice]]s to maintain and channel the water, along with systems of [[gears]], or toothed-wheels made of wood and metal to regulate the speed of rotation. More sophisticated small devices, such as the [[Antikythera Mechanism]] used complex trains of gears and dials to act as calendars or predict astronomical events. In a poem by [[Ausonius]] in the 4th century AD, he mentions a stone-cutting saw powered by water. [[Hero of Alexandria]] is credited with many such [[wind]] and [[steam]] powered machines in the 1st century AD, including the [[Aeolipile]] and the [[vending machine]], often these machines were associated with worship, such as animated altars and automated temple doors.

=== Medieval ===
Medieval Muslim engineers employed [[gear]]s in mills and water-raising machines, and used [[dam]]s as a source of water power to provide additional power to watermills and water-raising machines.<ref name="Hassan">{{cite book|first1=Ahmad Y. |last1=Hassan |author-link1=Ahmad Y. Hassan |chapter-url=http://www.history-science-technology.com/Articles/articles%2071.htm |title=Transfer of Islamic Technology to the West, Part II |chapter=Transmission of Islamic Engineering |archive-url=https://web.archive.org/web/20080218171021/http://www.history-science-technology.com/Articles/articles%2071.htm |archive-date=2008-02-18 }}</ref> In the [[Islamic Golden Age|medieval Islamic world]], such advances made it possible to [[Mechanization|mechanize]] many industrial tasks previously carried out by [[manual labour]].

In 1206, [[al-Jazari]] employed a [[Crank (mechanism)|crank]]-[[conrod]] system for two of his water-raising machines. A rudimentary [[steam turbine]] device was described by [[Taqi al-Din Muhammad ibn Ma'ruf|Taqi al-Din]]<ref name="Hassan1">[[Ahmad Y Hassan|Hassan, Ahmad Y.]] (1976). ''Taqi al-Din and Arabic Mechanical Engineering'', pp. 34–35. Institute for the History of Arabic Science, [[University of Aleppo]].</ref> in 1551 and by [[Giovanni Branca]]<ref name="Giovanni">{{cite web|url=http://www.history.rochester.edu/steam/thurston/1878/Chapter1.html |title=University of Rochester, NY, ''The growth of the steam engine'' online history resource, chapter one |publisher=History.rochester.edu |access-date=2010-02-03 |archive-url=https://web.archive.org/web/20120204034636/http://www.history.rochester.edu/steam/thurston/1878/Chapter1.html |archive-date=2012-02-04 }}</ref> in 1629.<ref>{{cite book |url=https://books.google.com/books?id=Cv9LH4ckuEwC&pg=PA432 |title=Power plant engineering |first=P.K. |last=Nag |year=2002 |publisher=[[Tata McGraw-Hill]] |page=432 |isbn=0-07-043599-5}}</ref>

In the 13th century, the solid [[rocket motor]] was invented in China. Driven by gunpowder, this simplest form of internal combustion engine was unable to deliver sustained power, but was useful for propelling weaponry at high speeds towards enemies in battle and for [[fireworks]]. After invention, this innovation spread throughout Europe.

=== Industrial Revolution ===
[[Image:Boulton and Watt centrifugal governor-MJ.jpg|thumb|upright|Boulton & Watt engine of 1788]]
The [[Watt steam engine]] was the first type of steam engine to make use of steam at a pressure just above [[atmospheric pressure|atmospheric]] to drive the piston helped by a partial vacuum. Improving on the design of the 1712 [[Newcomen steam engine]], the Watt steam engine, developed sporadically from 1763 to 1775, was a great step in the development of the steam engine. Offering a dramatic increase in [[fuel efficiency]], [[James Watt]]'s design became synonymous with steam engines, due in no small part to his business partner, [[Matthew Boulton]]. It enabled rapid development of efficient semi-automated factories on a previously unimaginable scale in places where waterpower was not available. Later development led to [[steam locomotive]]s and great expansion of [[Rail transport|railway transportation]].

As for internal combustion [[piston engine]]s, these were tested in France in 1807 by [[de Rivaz]] and independently, by the [[Nicéphore Niépce|Niépce brothers]]. They were theoretically advanced by [[Nicolas Léonard Sadi Carnot|Carnot]] in 1824.{{citation needed|date=May 2011}} In 1853–57 [[Eugenio Barsanti]] and [[Felice Matteucci]] invented and patented an engine using the free-piston principle that was possibly the first 4-cycle engine.<ref>{{cite web|title=La documentazione essenziale per l'attribuzione della scoperta|url=http://www.barsantiematteucci.it/inglese/documentiStorici.html|quote=A later request was presented to the Patent Office of the Reign of Piedmont, under No. 700 of Volume VII of that Office. The text of this patent request is not available, only a photo of the table containing a drawing of the engine. This may have been either a new patent or an extension of a patent granted three days earlier, on 30 December 1857, at Turin.|access-date=24 February 2014|archive-date=25 February 2017|archive-url=https://web.archive.org/web/20170225042248/http://www.barsantiematteucci.it/inglese/documentiStorici.html}}</ref>

The invention of an [[internal combustion engine]] which was later commercially successful was made during 1860 by [[Etienne Lenoir]].<ref>Victor Albert Walter Hillier, Peter Coombes – [https://books.google.com/books?id=DoYaRsNFlEYC&dq=cc+engine&pg=PA34 ''Hillier's Fundamentals of Motor Vehicle Technology'', Book 1] Nelson Thornes, 2004  {{ISBN|0-7487-8082-3}} [Retrieved 2016-06-16]</ref>

In 1877, the [[Otto cycle]] was capable of giving a far higher [[power-to-weight ratio]] than steam engines and worked much better for many transportation applications such as cars and aircraft.

[[File:Mercedes V6 DTM Rennmotor 1996.jpg|thumb|upright=1.2|A V6 [[internal combustion engine]] from a [[Mercedes-Benz]]]]

=== Automobiles ===
The first commercially successful automobile, created by [[Karl Benz]], added to the interest in light and powerful engines. The lightweight gasoline internal combustion engine, operating on a four-stroke Otto cycle, has been the most successful for light automobiles, while the thermally more-efficient [[Diesel engine]] is used for trucks and buses. However, in recent years, [[turbocharged]] Diesel engines have become increasingly popular in automobiles, especially outside of the United States, even for quite small cars.

==== Horizontally-opposed pistons ====
In 1896, Karl Benz was granted a patent for his design of the first engine with horizontally opposed pistons. His design created an engine in which the corresponding pistons move in horizontal cylinders and reach top dead center simultaneously, thus automatically balancing each other with respect to their individual momentum. Engines of this design are often referred to as “flat” or “boxer” engines due to their shape and low profile. They were used in the [[Volkswagen Beetle]], the [[Citroën 2CV]], some Porsche and Subaru cars, many [[BMW]] and [[Honda]] [[motorcycle]]s.  Opposed four- and six-cylinder engines continue to be used as [[aircraft engine|a power source]] in small, [[propeller (aeronautics)|propeller-driven]] [[aircraft]].

==== Advancement ====
The continued use of internal combustion engines in automobiles is partly due to the improvement of engine control systems, such as on-board computers providing engine management processes, and electronically controlled fuel injection. Forced air induction by turbocharging and supercharging have increased the power output of smaller displacement engines that are lighter in weight and more fuel-efficient at normal cruise power. Similar changes have been applied to smaller Diesel engines, giving them almost the same performance characteristics as gasoline engines. This is especially evident with the popularity of smaller diesel engine-propelled cars in Europe.  Diesel engines produce lower [[hydrocarbon]] and {{CO2}} emissions, but greater [[Atmospheric particulate matter|particulate]] and {{NOx|link=yes}} pollution, than gasoline engines.<ref name=Harrison2001>{{Citation |title= Pollution: Causes, Effects and Control |first= Roy M. |last= Harrison |author-link=Roy M. Harrison|edition=4th |publisher= [[Royal Society of Chemistry]] |year= 2001 |isbn= 978-0-85404-621-8 }}</ref> Diesel engines are also 40% more fuel efficient than comparable gasoline engines.<ref name=Harrison2001/>

==== Increasing power ====
In the first half of the 20th century, a trend of increasing engine power occurred, particularly in the U.S. models.{{Clarify|reason=As opposed to what models?|date=June 2012}} Design changes incorporated all known methods of increasing engine capacity, including increasing the pressure in the cylinders to improve efficiency, increasing the size of the engine, and increasing the rate at which the engine produces work. The higher forces and pressures created by these changes created engine vibration and size problems that led to stiffer, more compact engines with V and opposed cylinder layouts replacing longer straight-line arrangements.

==== Combustion efficiency ====
Optimal combustion efficiency in passenger vehicles is reached with a coolant temperature of around {{convert|230|F|C|order=flip|0}}.<ref>{{Cite web|last=McKnight|first=Bill|date=August 2017|title=The Electrically Assisted Thermostat|url=https://www.motor.com/magazine-summary/electrically-assisted-thermostat|url-status=live|access-date=2021-03-13|website=Motor.com|language=en-US|archive-date=2021-05-03|archive-url=https://web.archive.org/web/20210503012608/https://www.motor.com/magazine-summary/electrically-assisted-thermostat}}</ref>

==== Engine configuration ====
Earlier automobile engine development produced a much larger range of engines than is in common use today. Engines have ranged from 1- to 16-cylinder designs with corresponding differences in overall size, weight, [[engine displacement]], and cylinder [[Bore (engine)|bores]]. Four cylinders and power ratings from 19 to 120&nbsp;hp (14 to 90&nbsp;kW) were followed in a majority of the models. Several three-cylinder, two-stroke-cycle models were built while most engines had straight or in-line cylinders. There were several V-type models and horizontally opposed two- and four-cylinder makes too. Overhead [[camshaft]]s were frequently employed. The smaller engines were commonly air-cooled and located at the rear of the vehicle; compression ratios were relatively low. The 1970s and 1980s saw an increased interest in improved [[Fuel economy in automobiles|fuel economy]], which caused a return to smaller V-6 and four-cylinder layouts, with as many as five valves per cylinder to improve efficiency. The [[Bugatti Veyron]] 16.4 operates with a [[W16 engine]], meaning that two [[V8 engine|V8]] cylinder layouts are positioned next to each other to create the W&nbsp;shape sharing the same crankshaft.

The largest internal combustion engine ever built is the [[Wärtsilä-Sulzer RTA96-C]], a 14-cylinder, 2-stroke turbocharged diesel engine that was designed to power the ''[[Emma Mærsk]]'', the largest container ship in the world when launched in 2006. This engine has a mass of 2,300 tonnes, and when running at 102&nbsp;rpm (1.7&nbsp;Hz) produces over 80 MW, and can use up to 250 tonnes of fuel per day.