Е. С. Закирова, П. А. Красавин Английский язык для технических вузов
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| AN INTERNAL COMBUSTION ENGINE
An internal combustion (IC) engine is an engine in which combustion of the fuel takes place in a confined space, so that expanding gases provide mechanical power and produce motion. The invention and development of the internal combustion engine in the 19th century had a profound impact on human life. The first commercially successful internal combustion engine was created by a Frenchman, Étienne Lenoir in 1860. It ran on coal gas, but worked on a cycle of operations, which did not include compression of the gas before ignition: as a result, it was not very efficient. Although various forms of internal combustion engines had been developed before the 19th century, their widespread adoption in a variety of applications began with the commercial drilling and production of petroleum. Generally using fossil fuel (mainly pe- troleum), these engines appeared in almost all vehicles in the late 19th century. The most significant distinction between modern internal combustion engines and the early designs is the use of compression and, in particular, in-cylinder compression. Modern internal combustion engines can be classified in a number of dif- ferent ways. According to the type of ignition, they can be divided into spark- ignition (SI) and compression-ignition (CI) engines. Depending on the engine cycle, they are four-stroke cycle and two-stroke cycle ones. A four-stroke cycle engine has four piston movements over two engine revolutions for each cycle. A two-stroke cycle engine has two piston movements over one revolution for each cycle. In accordance with the valve location, the internal combustion engines are called I-head engines if valves are in head (overhead valve), and L-head engines if valves are in block (flat head). According to the type of cool- ing, engines can be classified as air-cooled engines and liquid-cooled engines (water-cooled engines). Basic design divides engines into reciprocating and rotary ones жүктеу/скачать 4,38 Mb. Достарыңызбен бөлісу:
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