Editing Diesel fuel (section)

== History ==
=== Origins ===
Diesel fuel originated from experiments conducted by German scientist and inventor [[Rudolf Diesel]] for his [[compression-ignition engine]] which he invented around 1892. Originally, Diesel did not consider using any specific type of fuel. Instead, he claimed that the operating principle of his [[Theory and Construction of a Rational Heat Motor|rational heat motor]] would work with any kind of fuel in any state of matter.<ref>{{patent|DE|67207|Rudolf Diesel: "Arbeitsverfahren und Ausführungsart für Verbrennungskraftmaschinen" pg 4.}}: "Alle Brennmaterialien in allen Aggregatzuständen sind für Durchführung des Verfahrens brauchbar."</ref> The first diesel engine prototype and the first functional Diesel engine were only designed for liquid fuels.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 125</ref>

At first, Diesel tested [[crude oil]] from [[Pechelbronn]], but soon replaced it with [[petrol]] and [[kerosene]], because crude oil proved to be too viscous,<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 107</ref> with the main testing fuel for the Diesel engine being kerosene ([[Mineral oil|paraffin]]).<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 108</ref> Diesel experimented with types of [[lamp oil]] from various sources, as well as types of petrol and [[ligroin]], which all worked well as Diesel engine fuels. Later, Diesel tested [[coal tar]] [[creosote]],<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 110</ref> paraffin oil, crude oil, [[gasoline]] and [[fuel oil]], which eventually worked as well.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 111</ref> In Scotland and France, [[shale oil]] was used as fuel for the first 1898 production Diesel engines because other fuels were too expensive.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 114</ref> In 1900, the French Otto society built a Diesel engine for the use with crude oil, which was exhibited at the [[Exposition Universelle (1900)|1900 Paris Exposition]]<ref name="Diesel_115">Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 115</ref> and the 1911 World's Fair in Paris.<ref>{{cite book |author=Ayhan Demirbas |title=Biodiesel: A Realistic Fuel Alternative for Diesel Engines |publisher=Springer |location=Berlin |year=2008 |pages=74 |isbn=978-1-84628-994-1 |url= https://books.google.com/books?id=0vBalrSH_OEC&q=Rudolf+Diesel+vegetable&pg=PA74}}</ref> The engine actually ran on [[peanut oil]] instead of crude oil, and no modifications were necessary for peanut oil operation.<ref name="Diesel_115" />

During his first Diesel engine tests, Diesel also used [[illuminating gas]] as fuel, and managed to build functional designs, both with and without pilot injection.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 116</ref> According to Diesel, neither was a coal-dust–producing industry existent, nor was fine, high-quality coal-dust commercially available in the late 1890s. This is the reason why the Diesel engine was never designed or planned as a coal-dust engine.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 126</ref> Only in December 1899, did Diesel test a coal-dust prototype, which used external mixture formation and liquid fuel pilot injection.<ref>Rudolf Diesel: ''Die Entstehung des Dieselmotors'', Springer, Berlin/Heidelberg 1913, {{ISBN|978-3-642-64940-0}} p. 127</ref> This engine proved to be functional, but suffered from piston ring failure after a few minutes due to coal dust deposition.<ref>Friedrich Sass: ''Geschichte des deutschen Verbrennungsmotorenbaues von 1860 bis 1918'', Springer, Berlin/Heidelberg 1962, {{ISBN|978-3-662-11843-6}} p. 499</ref>

=== Since the 20th century ===

Before diesel fuel was standardised, diesel engines typically ran on cheap fuel oils. In the United States, these were distilled from petroleum, whereas in Europe, coal-tar creosote oil was used. Some diesel engines were fuelled with mixtures of fuels, such as petrol, kerosene, rapeseed oil, or lubricating oil which were cheaper because, at the time, they were not being taxed.<ref>Hans Christian Graf von Seherr-Thoß (auth.): Die Technik des MAN Nutzfahrzeugbaus. In: MAN Nutzfahrzeuge AG (ed.): Leistung und Weg: Zur Geschichte des MAN Nutzfahrzeugbaus. Springer, Berlin/Heidelberg 1991. {{ISBN|978-3-642-93490-2}}. p. 436</ref> The introduction of motor-vehicle diesel engines, such as the [[Mercedes-Benz OM 138]], in the 1930s meant that higher-quality fuels with proper ignition characteristics were needed. At first no improvements were made to motor-vehicle diesel fuel quality. After World War II, the first modern high-quality diesel fuels were standardised. These standards were, for instance, the DIN 51601, VTL 9140–001, and NATO F 54 standards.<ref name="Seher-Thoß_437">Hans Christian Graf von Seherr-Thoß (auth.): Die Technik des MAN Nutzfahrzeugbaus. In: MAN Nutzfahrzeuge AG (ed.): Leistung und Weg: Zur Geschichte des MAN Nutzfahrzeugbaus. Springer, Berlin/Heidelberg 1991. {{ISBN|978-3-642-93490-2}}. p. 437</ref> In 1993, the DIN 51601 was rendered obsolete by the new EN 590 standard, which has been used in the European Union ever since. In sea-going watercraft, where diesel propulsion had gained prevalence by the late 1970s due to increasing fuel costs caused by the [[1970s energy crisis]], cheap [[heavy fuel oil]]s are still used instead of conventional motor-vehicle diesel fuel. These heavy fuel oils (often called [[Bunker C]]) can be used in diesel-powered and steam-powered vessels.<ref name="Mau_13">Günter Mau: Handbuch Dieselmotoren im Kraftwerks- und Schiffsbetrieb, Springer-Vieweg, Braunschweig/Wiesbaden 1984, {{ISBN|978-3-528-14889-8}}. p. 13</ref>