What is a diesel engine? How does it work?
What is a diesel engine?
A diesel engine is a type of internal combustion engine that uses compression ignition to turn energy in diesel fuel to rotary mechanical energy. The diesel engine was named after its inventor, Rudolf Diesel, who was born in Paris in 1858. The first diesel engine was prototyped in 1893 and originally designed to run on peanut oil.
Diesel fuel was so named because it was used to run diesel engines, diesel engines were not named after the fuel, which at the time of the first diesel engine, was a useless byproduct of extracting paraffin and kerosene from crude oil. In 1894 this waste product was finally named "diesel".
How does a diesel engine work?
A diesel engine works by using pistons to compress a mixture of air (containing oxygen) with diesel fuel. When this air is compressed at a ratio of about 15:1 the mixture explodes forcing the piston back up and creating the reciprocating motion. This motion is then converted to rotary motion by the engines crank shaft.
What are the major components in a diesel engine?
The engines fuel System
The fuel system includes the fuel injection pump, the lift pump, the injectors and all the fuel pipes. There will also be some fuel filters and maybe a water separator preventing poor quality fuel from damaging your diesel engine.
The engines lubrication system / oil system
The lubrication system keeps your engine running smoothly, preventing the moving parts from wearing by using the oil under pressure to lubricate and reduce friction. The oil system will have an oil pump and oil filters to keep the oil clean from contaminants.
The engines cooling system
The cooling system handles the engine coolant - normally a mixture of distilled water and glycol with some additional additives to help prevent corrosion. There may also be a coolant filter on some engines and a "water pump" which is actually a coolant pump. The coolant pump is used to push the coolant round the engine and whichever device is used to cool the liquid - usually a radiator, but sometimes a heat exchanger.
The engines exhaust system
Getting rid of the waste combustion gas is very important - moving the waste gas from the engines cylinders out through the exhaust manifold to the main muffler system that reduces the noise. The muffler isn't usually part of the engine, but an addition to reduce the noise to the customers requirements. The exhaust gas will pass through the turbo-charger to make it spin where one is fitted.
The engines Turbo charger
Most engines will have a turbo fitted. This device compresses the combustion air to make the engine more powerful.
A diesel engine is made from hundreds of component parts, but what are the major parts of a diesel engine?