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A steam turbine is a device which extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Sir Charles Parsons in 1884.〔A Stodola (1927) ''Steam and Gas Trubines''. McGraw-Hill.〕 Because the turbine generates rotary motion, it is particularly suited to be used to drive an electrical generator – about 90% of all electricity generation in the United States (1996) is by use of steam turbines. The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. ==History== The first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile, described in the 1st century by Greek mathematician Hero of Alexandria in Roman Egypt.〔turbine. Encyclopædia Britannica Online〕〔A new look at Heron's 'steam engine'" (1992-06-25). Archive for History of Exact Sciences 44 (2): 107-124.〕〔O'Connor, J. J.; E. F. Robertson (1999). Heron of Alexandria. MacTutor〕 In 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit. Steam turbines were also described by the Italian Giovanni Branca (1629)〔"''(Power plant engineering )''". P. K. Nag (2002). Tata McGraw-Hill. p.432. ISBN 978-0-07-043599-5〕 and John Wilkins in England (1648).〔(Taqi al-Din and the First Steam Turbine, 1551 A.D. ), web page, accessed on line October 23, 2009; this web page refers to Ahmad Y Hassan (1976), ''Taqi al-Din and Arabic Mechanical Engineering'', pp. 34-5, Institute for the History of Arabic Science, University of Aleppo.〕 The devices described by Taqi al-Din and Wilkins are today known as steam jacks. The modern steam turbine was invented in 1884 by Sir Charles Parsons, whose first model was connected to a dynamo that generated 7.5 kW (10 hp) of electricity.〔() 〕 The invention of Parsons' steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare.〔() 〕 Parsons' design was a reaction type. His patent was licensed and the turbine scaled-up shortly after by an American, George Westinghouse. The Parsons turbine also turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, and the size of generators had increased from his first 7.5 kW set up to units of 50,000 kW capacity. Within Parson's lifetime, the generating capacity of a unit was scaled up by about 10,000 times, and the total output from turbo-generators constructed by his firm C. A. Parsons and Company and by their licensees, for land purposes alone, had exceeded thirty million horse-power.〔 A number of other variations of turbines have been developed that work effectively with steam. The ''de Laval turbine'' (invented by Gustaf de Laval) accelerated the steam to full speed before running it against a turbine blade. De Laval's impulse turbine is simpler, less expensive and does not need to be pressure-proof. It can operate with any pressure of steam, but is considerably less efficient. :fr:Auguste Rateau developed a pressure compounded impulse turbine using the de Laval principle as early as 1896,〔https://books.google.co.uk/books?id=mwkIBgAAQBAJ&pg=PA9&lpg=PA9&dq=Rateau+1896&source=bl&ots=b8hxVrEMpC&sig=OoVAnvt0qFubqTmJxxahQB_xXPM&hl=en&sa=X&ved=0ahUKEwiDwbKGk6rJAhVBDxQKHbClDIkQ6AEIJjAE#v=onepage&q=Rateau%201896&f=false〕 obtained a US patent in 1903, and applied the turbine to a French torpedo boat in 1904. He taught at the École des mines de Saint-Étienne for a decade until 1897, and later founded a successful company that was incorporated into the Alstom firm after his death. One of the founders of the modern theory of steam and gas turbines was Aurel Stodola, a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute (now ETH) in Zurich. His work ''Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen'' (English: The Steam Turbine and its prospective use as a Mechanical Engine) was published in Berlin in 1903. A further book ''Dampf und Gas-Turbinen'' (English: Steam and Gas Turbines) was published in 1922. The ''Brown-Curtis turbine'', an impulse type, which had been originally developed and patented by the U.S. company International Curtis Marine Turbine Company, was developed in the 1900s in conjunction with John Brown & Company. It was used in John Brown-engined merchant ships and warships, including liners and Royal Navy warships. 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「Steam turbine」の詳細全文を読む スポンサード リンク
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