Rudolf Diesel, in full Rudolf Christian Karl Diesel

Rudolf Diesel, in full Rudolf Christian Karl Diesel, (born March 18, 1858, Paris, France—died September 29, 1913, at sea in the English Channel), German thermal engineer who invented the internal-combustion engine that bears his name. He was also a distinguished connoisseur of the arts, a linguist, and a social theorist.

Rudolf Diesel

QUICK FACTS



BORN

March 18, 1858

Paris, France

DIED

September 29, 1913 (aged 55)

Atlantic Ocean

INVENTIONS

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  diesel engine
  

Diesel, the son of German-born parents, grew up in Paris until the family was deported to England in 1870 following the outbreak of the Franco-German War. From LondonDiesel was sent to Augsburg, his father’s native town, to continue his schooling. There and later at the Technische Hochschule (Technical High School) in Munich he established a brilliant scholastic record in fields of engineering. At Munich he was a protégé of the refrigeration engineer Carl von Linde, whose Paris firm he joined in 1880.

Diesel devoted much of his time to the self-imposed task of developing an internal combustion engine that would approach the theoretical efficiency of the Carnot cycle. For a time he experimented with an expansion engine using ammonia. About 1890, in which year he moved to a new post with the Linde firm in Berlin, he conceived the idea for the diesel engine. He obtained a German development patent in 1892 and the following year published a description of his engine under the title Theorie und Konstruktion eines rationellen Wäremotors (Theory and Construction of a Rational Heat Motor). With support from the Maschinenfabrik Augsburg and the Krupp firms, he produced a series of increasingly successful models, culminating in his demonstration in 1897 of a 25-horsepower, four-stroke, single vertical cylinder compression engine. The high efficiency of Diesel’s engine, together with its comparative simplicity of design, made it an immediate commercial success, and royalty fees brought great wealth to its inventor.

Diesel disappeared from the deck of the mail steamer Dresden en route to London and was assumed to have drowned.

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Rudolf Christian Karl Diesel (German: [ˈdiːzl̩] (listen (help·info)); 18 March 1858 – 29 September 1913) was a German inventor and mechanical engineer, famous for the invention of the Diesel engine, and for his suspicious death at sea. Diesel was the namesake of the 1942 film Diesel.

Only few weeks after his birth, Diesel was given away to a Vincennes farmer family, where he spent his first nine months. When he was returned to his family, they moved into the flat 49 in the Rue Fontaineau-Roi. At the time, the Diesel family suffered from financial difficulties, thus young Rudolf Diesel had to work in his father's workshop and deliver leather goods to customers using a barrow. He attended a Protestant-French school and soon became interested in social questions and technology.[5] Being a very good student, 12-year-old Diesel received the Société pour l'Instruction Elémentaire bronze medal and had plans to enter Ecole Primaire Supérieure in 1870.[6]

At the outbreak of the Franco-Prussian Warthe same year, his family was forced to leave, as were many other Germans. They settled in London, England, where Diesel attended an English school.[7] Before the war's end, however, Diesel's mother sent 12-year-old Rudolf to Augsburg to live with his aunt and uncle, Barbara and Christoph Barnickel, to become fluent in German and to visit the Königliche Kreis-Gewerbeschule (Royal County Vocational College), where his uncle taught mathematics.

At the age of 14, Diesel wrote a letter to his parents saying that he wanted to become an engineer. After finishing his basic education at the top of his class in 1873, he enrolled at the newly founded Industrial School of Augsburg. Two years later, he received a merit scholarship from the Royal Bavarian Polytechnic of Munich, which he accepted against the wishes of his parents, who would rather have seen him start to work.

One of Diesel's professors in Munich was Carl von Linde. Diesel was unable to graduate with his class in July 1879 because he fell ill with typhoid fever. While waiting for the next examination date, he gained practical engineering experience at the Gebrüder Sulzer Maschinenfabrik (Sulzer Brothers Machine Works) in Winterthur, Switzerland. Diesel graduated in January 1880 with highest academic honours and returned to Paris, where he assisted his former Munich professor, Carl von Linde, with the design and construction of a modern refrigeration and ice plant. Diesel became the director of the plant one year later.

In 1883, Diesel married Martha Flasche, and continued to work for Linde, gaining numerous patents in both Germany and France.[8]

In early 1890, Diesel moved to Berlin with his wife and children, Rudolf Jr, Heddy, and Eugen, to assume management of Linde's corporate research and development department and to join several other corporate boards there. As he was not allowed to use the patents he developed while an employee of Linde's for his own purposes, he expanded beyond the field of refrigeration. He first worked with steam, his research into thermal efficiency and fuel efficiency leading him to build a steam engine using ammoniavapour. During tests, however, the engine exploded and almost killed him. His research into high compression cylinder pressures tested the strength of iron and steel cylinder heads. One exploded during a run in. He spent many months in a hospital, followed by health and eyesight problems.

Ever since attending lectures of Carl von Linde, Diesel intended designing an internal combustion engine based on the more thermally efficient Carnot cycle. He worked on this idea for a several years, and in 1892, he considered his theory to be completed. The same year, Diesel was given the German patent DRP 67207.[9] In 1893, he published a treatise entitled Theorie und Konstruktion eines rationellen Wärmemotors zum Ersatz der Dampfmaschine und der heute bekannten Verbrennungsmotoren [Theory and Construction of a Rational Heat-engine to Replace the Steam Engine and The Combustion Engines Known Today], that he had been working on since early 1892.[10] This treatise formed the basis for his work on and invention of the Diesel engine. By summer 1893, Diesel had realised that his initial theory was erroneous, which led him to file another patent application for the corrected theory in 1893.[9]

Diesel understood thermodynamics and the theoretical and practical constraints on fuel efficiency. He knew that as much as 90% of the energy available in the fuel is wasted in a steam engine. His work in engine design was driven by the goal of much higher efficiency ratios. In his engine, fuel was injected at the end of compression and the fuel was ignited by the high temperature resulting from compression. From 1893 to 1897, Heinrich von Buz, director of MAN AG in Augsburg, gave Rudolf Diesel the opportunity to test and develop his ideas.[2]

The first successful Diesel engine ran in 1897 and is now on display at the Deutsches Technikmuseum in Munich.

Rudolf Diesel obtained patents for his design in Germany and other countries, including the United States.[11][12]

He was inducted into the Automotive Hall of Fame in 1978.

On the evening of 29 September 1913, Diesel boarded the GER steamer SS Dresden in Antwerp on his way to a meeting of the Consolidated Diesel Manufacturing company in London, England. He took dinner on board the ship and then retired to his cabin at about 10 p.m., leaving word to be called the next morning at 6:15 a.m.; but he was never seen alive again. In the morning his cabin was empty and his bed had not been slept in, although his nightshirt was neatly laid out and his watch had been left where it could be seen from the bed. His hat and neatly folded overcoat were discovered beneath the afterdeck railing.[13]

Ten days later, the crew of the Dutch boat Coertzen came upon the corpse of a man floating in the North Sea near Norway. The body was in such an advanced state of decomposition that it was unrecognizable, and they did not bring it aboard. Instead, the crew retrieved personal items (pill case, wallet, I.D. card, pocketknife, eyeglass case) from the clothing of the dead man, and returned the body to the sea. On 13 October, these items were identified by Rudolf's son, Eugen Diesel, as belonging to his father. On 14 October 1913 it was reported that Diesel's body was found at the mouth of the Scheldtby a boatman, but he was forced to throw it overboard because of heavy weather.[14]

There are various theories to explain Diesel's death. Certain people, such as his biographer Grosser in 1978,[3] argue that Rudolf Diesel committed suicide. Another line of thought suggests that he was murdered, given his refusal to grant the German forces the exclusive rights to using his invention; indeed, Diesel boarded the SS Dresden with the intent of meeting with representatives of the British Royal Navy to discuss the possibility of powering British submarines by Diesel engine[15] – he never made it ashore. Yet, evidence is limited for all explanations, and his disappearance and death remain unsolved.

Shortly after Diesel's disappearance, his wife Martha opened a bag that her husband had given to her just before his ill-fated voyage, with directions that it should not be opened until the following week. She discovered 200,000 German marks in cash (US$1.2 million today) and a number of financial statements indicating that their bank accounts were virtually empty.[16] In a diary Diesel brought with him on the ship, for the date 29 September 1913, a cross was drawn, possibly indicating death.[13]