ENGINE TYPES
The types of engines that exist today come from different advances in different fields of science. However, it is well known that the first form of engine in existence was using steam. The steam engine replaced the horse. Electric and gasoline engines replaced steam engines.
There are many types of engines in the automotive world. More so now with the increasing development of electric cars that are transforming the market. But within the traditional combustion engines, there is already a huge list of engines with very different characteristics: diesel, gasoline, gas and even alcohol. Piston, rotary, four-stroke and two-stroke engines. The possibilities are almost innumerable.
GASOLINE ENGINES
Gasoline engines, also known as four-stroke engines, are those that work with a thermodynamic base that transform the chemical energy of ignition, caused by the mixture of air and fuel, into mechanical energy. In this way, the vehicle obtains the necessary energy to carry out its movements.
Gasoline engines operate in four-stroke cycles that can be roughly classified as follows:
- Intake phase: the intake valve opens, allowing the air-fuel mixture to flow into the cylinders.
- Compression phase: during this phase, the valve closes and the piston rises to compress the mixture.
- Explosion phase: the spark plugs create the spark necessary to produce the explosion and the descent of the pistons.
Exhaust phase: the exhaust valve opens and the pistons rise to expel the burnt gases to the outside.
DIESEL ENGINES
In general, diesel engines are mainly used in means of transportation that require an extra dose of power and are designed for a higher daily workload, such as industrial vehicles, cargo vehicles, machinery, aeronautical vehicles, etc.
Diesel engines work in a similar way to gasoline engines and their process can be equally divided into four stages, which are:
- Intake phase: air filling takes place and the intake valve remains open while the piston descends towards bottom dead center.
- Compression phase: the intake valve closes when the piston reaches bottom dead center and begins its travel to the top, compressing the air inside the cylinder.
- Combustion phase: the injector sprays the fuel into the chamber, which immediately ignites on contact with the hot air.
- Exhaust phase: the burned gases are expelled and inertia is allowed to restart the cycle.
ELECTRIC MOTORS
Although it may not seem so, electric motors predate four-stroke diesel or gasoline engines. Robert Anderson developed the first car with a pure electric motor, capable of transforming electrical energy into mechanical energy by means of the magnetic fields it generates, without the need for explosions or combustion typical of gasoline and diesel engines.
When we think of pure electric vehicles, we usually refer to BEVs, or battery electric vehicles. However, in the market we can find other options such as FCEVs, fuel cell vehicles, which are combined with hydrogen, and HEVs and PHEVs, known as hybrids and plug-in hybrids respectively, which alternate a permanent magnet electric motor with an internal combustion engine (mainly gasoline).
LPG AND CNG ENGINES
Vehicles that run on alternative fuels such as LPG (liquefied petroleum gas) or CNG (compressed natural gas) are gaining ground in the automotive industry, and more and more manufacturers are betting on marketing versions of some of their models powered by this type of fuel.
Either of the two options, LPG or CNG, favor the increase of the useful life of the engine, since they do not generate so much wear in the cylinders and less waste is deposited in the system. However, it must be taken into account that sometimes it makes lubrication more difficult and can deteriorate the valves at higher speeds, something that can be solved thanks to preventive mechanics and good maintenance.
