Internal Combustion Engines Essay -- Engine Cars Mechanics Essays

Internal Combustion EnginesAn internal- burning engine is a heat engine that burns fuel and air at bottom a burning bedroom set(p) within the engine proper. Simply stated, aheat engine is an engine that converts heat energy to mechanical energy. Theinternal- combustion engine should be distinguished from the external-combustion engine, for example, the steam engine and the Stirling engine, whichburns fuel outside the prime mover, that is, the device that actually producesmechanical motion. Both introductory types produce hot, expanding gases, which may hencebe employed to move pistons, turn turbine rotors, or cause locomotion throughthe reaction principle as they secede through the nozzle.Most people are familiar with the internal-combustion reciprocating engine,which is used to former most automobiles, boats, lawn mowers, and home generators.Based on the means of ignition, two types of internal-combustion reciprocatingengines can be distinguished spark-ignition engines and co mpression-ignitionengines. In the former, a spark ignites a combustible mixture of air and fuelin the latter, high compression raises the temperature of the air in the chamberand ignites the injected fuel without a spark. The diesel engine is acompression-ignition engine. This article emphasizes the spark-ignition engine.The invention and early development of internal-combustion engines areusually credited to three Germans. Nikolaus Otto patented and built (1876) thefirst such engine Karl Benz built the first automobile to be powered by such anengine (1885) and Gottlieb Daimler designed the first high-speed internal-combustion engine (1885) and carburetor. Rudolf Diesel invented a successfulcompression-ignition engine (the diesel engine) in 1892.The operation of the internal-combustion reciprocating engine employseither a tetrad-stroke cycle or a two-stroke cycle. A stroke is one continuousmovement of the piston within the cylinder.In the four-stroke cycle, also known as the Otto cycle, the downwardmovement of a piston located within a cylinder creates a partial vacuum. Valveslocated inside the combustion chamber are controlled by the motion of a camshaftconnected to the crankshaft. The four strokes are called, in order of sequence,intake, compression, power, and exhaust. On the first stroke the intake valve isopened w... ... energy within themuffler before the exhaust gases are permitted to escape.The power capacity of an engine depends on a number of characteristics,including the volume of the combustion chamber. The volume can be increased byincreasing the size of the piston and cylinder and by increasing the number ofcylinders. The cylinder configuration, or arrangement of cylinders, can bestraight, or in-line (one cylinder located behind the other) radial (cylinderslocated around a circle) in a V (cylinders located in a V configuration) oropposed (cylinders located opposite each other). other type of internal-combustion engine, the Wankel engine, has no cylinders instead, it has a rotorthat moves through a combustion chamber.An internal-combustion engine must also have some kind of transmittingsystem to control and direct the mechanical energy where it is needed forexample, in an automobile the energy must be directed to the driving wheels.Since these engines are not able to start under a load, a transmission systemmust be used to disengage the engine from the load during starting and then toapply the load when the engine reaches its operating speed.