Internal combustion engine

An internal combustion engine is a type of internal combustion engine that uses the explosion of a fuel, ignited by a spark, to expand a gas that pushes a piston, which is Attached to the crankshaft by a connecting rod, this acts as a crank and transforms the linear movement of the piston into rotation in the crankshaft. The thermodynamic cycle used is known as the Otto cycle. There are two-stroke and four-stroke internal combustion engines.

This engine, also called the gasoline engine or Otto engine, is, together with the diesel engine, the most widely used today to drive autonomous vehicles for transporting goods and people.

The fuel that is traditionally used in an internal combustion engine is gasoline. Currently, some internal combustion engines can also run on ethanol, compressed natural gas, liquefied petroleum gas or hydrogen, in addition to gasoline.

In countries like Spain, more gasoline engines are used for the use of CNG (Compressed Natural Gas), which in addition to being economical, damages the ecosystem less.

• Otto conventional cycle motor
• Miller Cycle Engine
• Poor mixing engine

Conventional operation (four times)

Fuel is injected pulverized and mixed with gas (usually air or oxygen) inside a cylinder. The total combustion of 1 gram of gasoline would theoretically be carried out with 14.7 grams of air, but since it is impossible to achieve a perfectly homogeneous mixture of both elements, 10% more air than necessary is usually introduced (weight ratio 1/16), sometimes more or less fuel is injected, this is determined by the lambda probe (or oxygen probe) which sends a signal to the ECU. Once inside the cylinder the mixture is compressed. Upon reaching the point of maximum compression (top dead center or PMS) a spark is fired, produced by a spark plug, which generates the explosion of the fuel. The gases enclosed in the cylinder expand by pushing a piston that slides inside the cylinder (theoretically adiabatic expansion of gases). The energy released in this explosion is transformed into the linear movement of the piston, which, through a connecting rod and the crankshaft, is converted into rotary movement. The inertia of this rotary movement means that the engine does not stop and that the piston pushes the gas again, expelling it through the corresponding valve, now open. Finally, the piston moves back again, allowing a new fuel mixture to enter.

History

Gasoline, which is obtained by the fractional distillation of petroleum, was discovered in 1857. Later, in 1860, Jean Joseph Etienne Lenoir created the first internal combustion engine by burning gas inside a cylinder. But it would take until 1867 for Nikolaus August Otto to build the first four-stroke gasoline engine in history, which was the basis for all subsequent internal combustion engines. In 1886 Karl Benz began to use gasoline engines in his first car prototypes.