Diesel fuel, also called diesel oil or historically heavy oil, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a result of compression of the inlet air and then injection of fuel. Therefore, diesel fuel needs good compression ignition characteristics.
A tank of diesel fuel on a truck
A modern diesel dispenser
Biodiesel made from soybean oil
Large diesel fuel tanks in Sörnäinen, Helsinki, Finland
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine. This contrasts with engines using spark plug-ignition of the air-fuel mixture, such as a petrol engine or a gas engine.
Diesel engine built by Langen & Wolf under licence, 1898
Rudolf Diesel's 1893 patent on a rational heat motor
Diesel's second prototype. It is a modification of the first experimental engine. On 17 February 1894, this engine ran under its own power for the first time. Effective efficiency 16.6% Fuel consumption 519 g·kW−1·h−1
First fully functional diesel engine, designed by Imanuel Lauster, built from scratch, and finished by October 1896. Rated power 13.1 kW Effective efficiency 26.2% Fuel consumption 324 g·kW−1·h−1.