Petrol engine
A petrol engine (gasoline engine in American and Canadian English) is an
Most petrol engines use spark ignition, unlike diesel engines which typically use compression ignition. Another key difference to diesel engines is that petrol engines typically have a lower compression ratio.
History
The first practical petrol engine was built in 1876 in Germany by Nicolaus August Otto, although there had been earlier attempts by Étienne Lenoir in 1860, Siegfried Marcus in 1864 and George Brayton in 1876.[citation needed]
Design
Thermodynamic cycle
Most petrol engines use either the four-stroke Otto cycle or the two-stroke cycle.[1][2][3] Petrol engines have also been produced using the Miller cycle and Atkinson cycle.[4][5][6][7]
Layout
Most petrol-powered piston engines are straight engines or V engines. However, flat engines, W engines and other layouts are sometimes used.
Wankel engines are classified by the number of rotors used.
Compression ratio
Cooling
Petrol engines are either air-cooled or water-cooled.
Ignition
Petrol engines use
Primer
Primers may be used to help start the engine. They can draw fuel from fuel tanks and vaporize fuel directly into piston cylinders. Engines are difficult to start during cold weather, and the fuel primer helps because otherwise there will not be enough heat available to vaporize the fuel in the carburetor.[8]
Power output and efficiency
The power output of small- and medium-sized petrol engines (along with equivalent engines using other fuels) is usually measured in kilowatts or horsepower.
Typically, petrol engines have a
Applications
Applications of petrol engines include
(such as lawn mowers, chainsaws and portable generators). Petrol engines have also been used as "pony engines", a type of engine used to start a larger, stationary diesel engine.See also
- Diesel engine
- Electric motor
- Hydrogen engine
- Jet engine
References
- ^ "What is Otto Cycle - Complete Explaintion on P-v & T-s Diagram". The Engineers Post. 10 September 2019. Retrieved 14 August 2022.
- ^ "What is Two Stroke Engine?- Types, And Working". Engineering Choice. 12 November 2020. Retrieved 14 August 2022.
- ^ "Two Stroke Engine - Internal Combustion Engines (IC) - Automobile Magazine". MotorTrend. 16 December 2009. Retrieved 14 August 2022.
- ^ "How does a Miller-cycle engine work?". HowStuffWorks. 1 April 2000. Retrieved 14 August 2022.
- ^ "Mazda 2.3L Miller-cycle DOHC V-6". WardsAuto. 1 January 1998. Retrieved 14 August 2022.
- ^ "Why does Toyota use Atkinson cycle engines?". Toyota UK Magazine. 14 January 2015. Retrieved 14 August 2022.
- ^ "Engine Types: Atkinson Cycle vs Otto vs Miller". EngineHoist. 4 April 2016. Retrieved 9 June 2023.
- ^ "Chapter 7: Aircraft Systems". Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25C ed.). Federal Aviation Administration. 2023-07-17. p. 25.
- ^ "Toyota Gasoline Engine Achieves Thermal Efficiency Of 38 Percent". Green Car Reports. Retrieved 2017-10-07.