Rudolf Diesel - The Inventor

6. September 2008 |

Rudolf Christian Karl Diesel March 18, 1858 – last seen alive September 29, 1913) was a German inventor and mechanical engineer, famous for the invention of the compression ignition engine that bears his name. The word “diesel” is derived from eponymous German inventor Rudolf Christian Karl Diesel (March 18, 1858 – September 30, 1913) who in 1892 invented the diesel engine. Diesel understood thermodynamics and the theoretical and practical constraints on fuel efficiency. He knew that even the best steam engines, of his era, were only 10-15% thermodynamically efficient. His work in engine design was driven by the goal of much higher efficiency ratios. He tried to design an engine based on the Carnot Cycle. However, he gave up on this, and eventually, designed his own engine, for which he received a patent. In his engine, fuel was injected at the end of the compression stroke, and the fuel was ignited by the high temperature resulting from this compression. In 1893, he published a book, in German, with the title “Theory and design of a rational thermal engine to replace the steam engine and the combustion engines known today” (English translation of the original title in German) with the help of Springer Verlag, Berlin. He managed to build a working engine according to his theory and design. His engine is now known as the diesel engine. Heinrich von Buz (1833-1918) was director (MAN AG) of an engine factory in Augsburg, Germany and from 1893-1897, he gave Rudolf Diesel the opportunity to test and develop his ideas. Rudolf Diesel obtained patents for his design in Germany and other countries including USA, for example, US Patent 542846 and US Patent 608845.

After Diesel’s death, the diesel engine underwent much development, and became a very important replacement for the steam piston engine in many applications. Because the diesel engine required a heavier, more robust construction than a gasoline engine, it was not widely used in aviation (but see aircraft diesel engine). However, the diesel engine became widespread in many other applications, such as stationary engines, submarines, ships, and much later, locomotives, trucks, and in modern automobiles. Diesel engines are most often found in applications where a high torque requirement and low RPM requirement exist. Because of their generally more robust construction and high torque, Diesel engines have also become the workhorses of the trucking industry. Recently, diesel engines that have overcome this weight penalty have been designed, certified and flown in light aircraft. These engines are designed to run on either Diesel fuel or more commonly jet fuel.

The diesel engine has the benefit of running more fuel-efficiently than gasoline engines. Diesel was especially interested in using coal dust or vegetable oil as fuel, and his engine in fact ran on peanut oil. Although these fuels were not immediately popular, recent rises in fuel prices coupled with concerns about oil reserves have led to more widespread use of vegetable oil and biodiesel. The primary source of fuel remains what became known as Diesel fuel, an oil byproduct derived from refinement of petroleum.