internal-combustion engine

internal-combustion engine
an engine of one or more working cylinders in which the process of combustion takes place within the cylinders.
[1880-85]

* * *

Any engine in which a fuel-air mixture is burned in the engine proper so that the hot gaseous products of combustion act directly on the surfaces of its moving parts, such as those of pistons (see piston and cylinder) or turbine rotor blades.

Internal-combustion engines include gasoline engines, diesel engines, gas turbine engines, pure jet engines, and rocket engines and motors, and are one class of heat engines. They are commonly divided into continuous-combustion engines and intermittent-combustion engines. In the first type (e.g., jet engines) fuel and air flow steadily into the engine, where a stable flame is maintained for continuous combustion. In the second (e.g., gasoline–reciprocating-piston engines), discrete quantities of fuel and air are periodically ignited. See also automobile industry, machine, steam engine.

* * *

      any of a group of devices in which the reactants of combustion (oxidizer and fuel) and the products of combustion serve as the working fluids of the engine. Such an engine gains its energy from heat released during the combustion of the nonreacted working fluids, the oxidizer-fuel mixture. This process occurs within the engine and is part of the thermodynamic cycle of the device. Useful work generated by an internal-combustion (IC) engine results from the hot gaseous products of combustion acting on moving surfaces of the engine, such as the face of a piston, a turbine blade, or a nozzle.

      Internal-combustion engines are the most broadly applied and widely used power-generating devices currently in existence. Examples include gasoline engines (gasoline engine), diesel engines (diesel engine), gas-turbine engines (gas-turbine engine), and rocket-propulsion systems.

      Internal-combustion engines are divided into two groups: continuous-combustion engines and intermittent-combustion engines. The continuous-combustion engine is characterized by a steady flow of fuel and oxidizer into the engine. A stable flame is maintained within the engine (e.g., jet engine). The intermittent-combustion engine is characterized by periodic ignition of air and fuel and is commonly referred to as a reciprocating engine. Discrete volumes of air and fuel are processed in a cyclic manner. Gasoline piston engines and diesel engines are examples of this second group.

      Internal-combustion engines can be delineated in terms of a series of thermodynamic events. In the continuous-combustion engine, the thermodynamic events occur simultaneously as the oxidizer and fuel and the products of combustion flow steadily through the engine. In the intermittent-combustion engine, by contrast, the events occur in succession and are repeated for each full cycle.

      With the exception of rockets (both solid rocket motors and liquid-propellant rocket engines), internal-combustion engines ingest air, then either compress the air and introduce fuel into the air or introduce fuel and compress the air-fuel mixture. Then, common to all internal-combustion engines, the air-fuel mixture is burned, work is extracted from the expansion of the hot gaseous products of combustion, and ultimately the products of combustion are released through the exhaust system. Their operation can be contrasted with that of external-combustion engines (e.g., steam engines (steam engine)), in which the working fluid does not chemically react and energy gain is achieved solely through heat transfer to the working fluid by way of a heat exchanger.

      The most common internal-combustion engine is the four-stroke, gasoline-powered, homogeneous-charge, spark-ignition engine. This is because of its outstanding performance as a prime mover in the ground transportation industry. Spark-ignition engines also are used in the aeronautics industry; however, aircraft gas turbines have become the prime movers in this sector because of the emphasis of the aeronautics industry on range, speed, and passenger comfort. The domain of internal-combustion engines also includes such exotic devices as supersonic combustion ramjet engines (scramjets), as typified by the space plane, and sophisticated rocket engines and motors, such as those used on U.S. space shuttles and other space vehicles.

Charles Lafayette Proctor II
 

* * *


Universalium. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Internal-combustion engine — Internal combustion engine) in which the heat or pressure energy necessary to produce motion is developed in the engine cylinder, as by the explosion of a gas, and not in a separate chamber, as in a steam engine boiler. The gas used may be a… …   The Collaborative International Dictionary of English

  • internal combustion engine — internal combustion engines N COUNT An internal combustion engine is an engine that creates its energy by burning fuel inside itself. Most cars have internal combustion engines …   English dictionary

  • internal-combustion engine — [in tʉr′nəlkəm bus′chənen′jən, in tʉrn′ lkəm bus′chən] n. an engine, as in an airplane, automobile, etc., that obtains its power from heat and pressure produced by the combustion of a fuel and air mixture inside a closed chamber or cylinder …   English World dictionary

  • internal-combustion engine — ► NOUN ▪ an engine in which power is generated by the expansion of hot gases from the burning of fuel with air inside the engine …   English terms dictionary

  • Internal combustion engine — The internal combustion engine is an engine in which the combustion of a fuel (normally a fossil fuel) occurs with an oxidizer (usually air) in a combustion chamber. In an internal combustion engine, the expansion of the high temperature and high …   Wikipedia

  • internal-combustion engine — noun a heat engine in which combustion occurs inside the engine rather than in a separate furnace; heat expands a gas that either moves a piston or turns a gas turbine • Syn: ↑ICE • Hypernyms: ↑heat engine • Hyponyms: ↑diesel, ↑diesel engine, ↑ …   Useful english dictionary

  • internal-combustion engine — UK / US noun [countable] Word forms internal combustion engine : singular internal combustion engine plural internal combustion engines science a type of engine used in most cars …   English dictionary

  • internal combustion engine — (IC) An engine that burns fuel within itself as a means of developing power (unlike an external combustion engine such as a steam engine). Although the term internal combustion engine covers all types of reciprocating and rotary engines, it is… …   Dictionary of automotive terms

  • internal-combustion engine — vidaus degimo variklis statusas T sritis fizika atitikmenys: angl. combustion motor; explosion engine; internal combustion engine vok. Explosionsmotor, m; Verbrennungskraftmaschine, f; Verbrennungsmotor, m rus. двигатель внутреннего сгорания, m… …   Fizikos terminų žodynas

  • Internal combustion engine —   An engine in which fuel is burned inside the engine. A car s gasoline engine or rotary engine is an example of a internal combustion engine. It differs from engines having an external furnace, such as a steam engine.   California Energy… …   Energy terms

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”