History Of The Steam Engine
The first reference of the steam engine is found in the Hellenistic period. Then we talk about experiments to take advantage of the expansion of the compounds due to the change of the liquid phase to the gas (vapor) phase: in particular, the Aeolus cell of the heron. It is a hollow metal sphere filled with water, with the arms tangential to the outlet hole: when water is heated, it vaporizes and the water vapor that comes out of the holes, by rotating the ball itself.
You should also remember the attempts to use Leonardo da Vinci's steam with his car called the Architano. In 1606 the Giovanni Battista della Porta experiments were able to use it as a driving force. The Salomon de Caus engineer also performed steam engine experiments similar to those of Della Porta. In 1615 Alomon Caus published a treatise on his system containing a steam bomb.
In more recent times, the first steam applications can be traced back to the experiments of Denis Papin and his pressure cooker of 1679. In this experiment he went to conceive ideas on how to develop the use of steam.
Origin of the first steam engine
The subsequent experiments took place at the beginning of the 18th century, especially for the pumping of water from the mines. The bomebo of the water was made by the system devised in 1698 by Thomas Savery using the vacuum created by the condensation of the steam introduced into a container. With this experiment it was possible to raise the water to approximately 10 m in height. Moreover, thanks to the invention of the cylinder-piston system (probably due to Denis Papin) it was possible to convert the steam energy into a mechanical movement. In this way a mechanical work was obtained and, therefore, the first steam engine.
First industrial applications of the steam engine
The first example of industrial application of this concept is the Newcomen steam engine, 1705. The Newcomen machine was large but not too powerful and expensive. I only managed to make a back and forth movement. For this reason, it is used to extract water from mines.
At first, the steam engine worked at low pressure, that is, steam was used immediately. Such qual left the boiler went to the cylinder. These steam engines were huge compared to the power supplied. For installation in self-propelled vehicles, therefore, a smaller and lighter steam engine design was required for the same power.
This problem led to the creation of high pressure steam machines. In high- pressure steam engines, pressure builds up inside the boiler instead of ejecting water vapor into the cylinder as it occurs. This goal was achieved later, thanks to the invention of the external capacitor. In the external condenser, the distribution of the drawers and crank-crank mechanism (which allows it to create a rotation movement instead of simply as an alternative until then) allowed to go from sporadic applications to a general use in transport and in the industry. The merits of such an event are attributed to James Watt in 1765.
Watt's invention made it possible to reduce the cost of the steam engine, reduce its size, reduce energy consumption and increase the available power. From the first model with 4.4 kW of power, locomotives of 0.4 MW have been passed in less than 20 years.
The steam engine in industry
The steam engine, allowed to have a greater power than could be obtained with the resources available until then. As an example, a running horse can produce 8 kW for short distances, but to work one day it can not produce more than 0.7 kW). This evolution has played a key role in the industrial revolution.
The development of the steam engine has facilitated the extraction and transport of coal. The reduction of the costs of coal exploitation contributes to lower the costs of the use of the steam engine. The second application of the steam engine was to move the bellows in foundries in 1776, while by 1787 it was also used to spin cOtton garments.
Last review: November 14, 2017