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Johann Stumpf of Technische Hochschule Charlottenburg (today Technische Universität Berlin) is best known for popularising the uniflow steam engine, in the years around 1909, and his name has always been associated with it. The basic uniflow principle had been invented many years before.
Stumpf's 'Uniflow' system aroused interest among engine designers in the years before the First World War, at first in his native Germany and later elsewhere. The Uniflow principle was known previously, and Stumpf's work was really its practical application. In Stumpf's system steam was admitted at one end of the cylinder, and the used steam left through a ring of ports at the other end of the cylinder. This allowed the admission end to stay hot, as it was not cooled by the exhaust on its way out, and so improved efficiency. In a double-acting engine the exhaust ports were in the middle of the cylinder.
Almost all uniflow engines were large stationary types, but the system was tried by, among others, the North Eastern Railway in England, as described by Tuplin (see sources). Briefly, the system worked well and obtained a small increase in economy by decreasing fuel consumption, but at the price structure prevailing at that time the extra constructional and maintenance costs were greater than the coal economy. H.W. Dickinson's A Short History of The Steam Engine makes it clear that the concept of the uniflow engine reached back to Montgolfier and Jacob Perkins (who patented the idea) and Leonard Jennett Todd (Patent No. 7801): Dickinson then gives Stumpf of Technische Hochschule Charlottenburg his due citing a paper by T.B. Perry Proc. Inst. Mech. Eng. , 1920 (1922?).
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A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be transformed, by a connecting rod and crank, into rotational force for work. The term "steam engine" is most commonly applied to reciprocating engines as just described, although some authorities have also referred to the steam turbine and devices such as Hero's aeolipile as "steam engines". The essential feature of steam engines is that they are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term steam engine can refer to either complete steam plants, such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine.
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William Hall Barnett is described as a 'founder' in his 1836 patent, and an 'ironfounder' in his 1838 patent, and later as an engineer and gas engineer, working in Brighton, UK. He worked for many years for the Brighton and Hove General Gas Company. He was born in Bradford and died in Brighton.
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Jacob Perkins was an American inventor, mechanical engineer and physicist based in the United Kingdom. Born in Newburyport, Massachusetts, Perkins was apprenticed to a goldsmith. He soon made himself known with a variety of useful mechanical inventions and eventually had twenty-one American and nineteen English patents.Sometimes known as the father of the refrigerator. He was elected a Fellow of the American Academy of Arts and Sciences in 1813 and a member of the American Philosophical Society in 1819.
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