Who invented Diesel Engine?

Rudolf Diesel, 1895

Rudolf Diesel remains well known today through the type of engine that bears his name, now widely used, and its distinctive fuel. Diesel should have made a fortune from his inventions, but had no head for business.

How Diesel Engine Invented?

Diesel trained as a refrigeration engineer in Munich; his exam results were the highest ever achieved. Steam engines, though much improved by James Watt and others, remained unacceptably inefficient, turning perhaps 15 percent of the energy in coal into useful work. They were also too big and costly. More efficient (therefore smaller) engines could power vehicles.

Etienne Lenoir and Nicolaus Otto had already created ‘internal combustion engines’ in which the fuel was burnt inside the cylinder rather than outside, as in a steam engine. Seeking greater efficiency in a ‘rational heat engine’, Diesel proposed injecting fuel into the cylinder and igniting it, not with a spark or flame, but by the high temperature generated as the piston compressed the air in the cylinder. By working through a much wider range of temperatures and pressures, his engines would exploit more of the energy of the burning fuel.

Diesel’s first engine, set running in 1893, was a failure. The intended fuel was coal dust; funding came from industry giants like steel magnate Baron von Krupp. The coal dust fuelled engine exploded during trials, nearly killing him.

A second model, also operational in 1893, used heavy fuel oil, less refined and therefore cheaper than petrol, his 1895 model had unprecedented fuel efficiency, opening up many applications. Diesel became famous. Within a few decades, diesel engines were powering factories, water pumps, automobiles and trains and ships.

Diesel engines have traditionally produced smoky exhaust fumes, posing risks to health and the environment, and poor acceleration, making them less popular than petrol engines. But more refined technology, especially in fuel injection, and better quality fuels have largely solved these problems, letting the inherent benefits of Rudolph Diesel’s creation shine through.