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The Brayton cycle is a thermodynamic cycle that describes the workings of a constant pressure heat engine. Gas turbine engines and airbreathing jet engines use the Brayton cycle. Although the Brayton cycle is usually run as an open system (and indeed ''must'' be run as such if internal combustion is used), it is conventionally assumed for the purposes of thermodynamic analysis that the exhaust gases are reused in the intake, enabling analysis as a closed system. The engine cycle is named after George Brayton (1830–1892), the American engineer who developed it, although it was originally proposed and patented by Englishman John Barber in 1791.〔according to (Gas Turbine History )〕 It is also sometimes known as the Joule cycle. The Ericsson cycle is similar to the Brayton cycle but uses external heat and incorporates the use of a regenerator. There are two types of Brayton cycles, open to the atmosphere and using internal combustion chamber or closed and using a heat exchanger. ==History== In 1872, George Brayton applied for a patent for his "Ready Motor," a reciprocating constant pressure engine. The engine used a separate piston compressor and expander, with compressed air heated by internal fire as it entered the expander cylinder. The first versions of the Brayton engine mixed vaporized fuel with air as it entered the compressor by means of a heated-surface carburetor., The fuel / air was contained in a reservoir / tank and then it was admitted to the expansion cylinder and burned. As the fuel / air mixture entered the expansion cylinder it was ignited by a pilot flame. A screen was used to prevent the fire from entering / returning to the reservoir. In early versions of the engine, this screen sometimes failed and an explosion would occur, but in 1874 Brayton solved the explosion problem by adding the fuel just prior to the expander cylinder. The engine now used heavier fuels such as kerosine and fuel oil. Ignition remained pilot flame. Brayton produced and sold "Ready Motors" to perform a variety of tasks like water pumping, mill operation, even marine propulsion. Critics of the day claimed the engines ran smoothly and had an efficiency of about 17%. Brayton cycle engines were some of the first internal combustion engines used for motive power. In 1881, John Holland used a Brayton engine to power the world's first successful self-propelled submarine, the Fenian Ram. John Philip Holland's submarine is preserved in the Paterson Museum in the Old Great Falls Historic District of Paterson, New Jersey.〔 〕 In 1878, George B. Selden produced the first internal combustion automobile. Inspired by the internal combustion engine invented by George Brayton displayed at the Centennial Exposition in Philadelphia in 1876, Selden began working on a smaller lighter version, succeeding by 1878, some eight years before the public introduction of the Benz Patent Motorwagen in Europe. The Selden auto was powered by a 3-cylinder, 400-pound version of the Brayton Cycle engine which featured an enclosed crankshaft. Selden designed and constructed the engine with the help of Rochester machinist Frank H. Clement and his assistant William Gomm. He filed for a patent on May 8, 1879 (in a historical cross of people, the witness Selden chose was a local bank-teller, George Eastman, later to become famous for the Kodak camera). His application included not only the engine but its use in a 4 wheeled car. He then filed a series of amendments to his application which stretched out the legal process resulting in a delay of 16 years before the patent〔 (patent.pdf )〕 was granted on November 5, 1895. Henry Ford fought the Selden patent. Ford argued his cars used the four-stroke Otto cycle and not the Brayton engine shown used in the Selden auto. Ford won the appeal of the original case. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Brayton cycle」の詳細全文を読む スポンサード リンク
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