An explosion is so violent that may appear impossible for man to dominate it completely and effectively. But explosions perfectly regulated are produced in the internal-combustion engine which satisfy today much of modern life's energy demand.

In 1794 R. Street suggested an engine impulsed with the explosion of turpentine and air. Douglas Clerk considers this as the first description made in England about a gas motor. En 1820 W. Cecil described a motor which worked with explosions of air and hydrogen to make a vacuum below a piston to generate a work with the help of gravity. This is considered as the first engine that worked with gas.

There are four types of internal-combustion engines:

Gas Engines

The commercial development of gas engine began in 1823 based on Samuel Brown's idea about vacuum and atmospheric preasure. Then Guillermo Barnett in 1838 realized the importance of gas compression before the ignition. In 1859 Barsanti and Matteucci made the free piston engine. Later, in 1861, G. Schmidt stated that engines would work better with a fuel compression of 3atm to get a bigger expansion of gases and increase the production of energy.

Beau de Rochas cycle.

In 1862 Beau de Rochas established the four conditions to obtain the best economy in the working

1. A cylinder of maximum volume with the minimum cooling area.

2. Maximum speed expansion

3. Maximum relation of expansion.

4. Maximum initial preasure of the ignited fuel.

And those conditions could be achieved with the following order.

1. Aspiration when the piston is moving backward.

2. Fuel compression.

3. Fuel ignition and expansion.

4. Escape of expanded gases.

14 years later, in 1876, Otto made an engine based on Rocha's conditions, it is now used in most of today's vehicles. In the four cycles engine there are two valves in each cilinder: admission and escape.

Gasoline Engines

Teofilo Daimler (1834-1900) got the credits for this important engine. In 1866 his engine worked at 800 r.p.m. and had a weight of 40kg (88.2lb) per h.p. compared with those of 200 r.p.m. that had a weight of 500kg (1102.5lb).

The advantages of Daimler engine where:

Starting System

The battery provides the electricity to ignitiate the fuel. But 6 or 12v can't do it alone, the bobbin multiplies those volts to 18 000 and the interrupter creates the spark.

Diesel Engine

In 1892, Rodolfo Diesel, german engineer, patented an internal combustion engine, named Diesel Engine, without the need to use a spark to ignitiate the engine's cycle; instead it uses high pressure compressors that warms the air to 538C, then fuel is injected and the combustion is made.

Diesel engines has the following advantages over gasoline engines:

And the following disadvantages: