Steam Engine

Steam Engine

Introduction

Steam engines are the combustion engines which work externally. The working fluid is separated from the products in the processes of external combustions. Steam Engines are the most widely used engines around the globe. The steam engine was invented by Thomas Newcomen in 1705 (Galloway, Elajah, 1828). James Watt made large improvements and modifications in these engines in 1769. Steam Engines are used in steam boats, factories and locomotives. They are serving as the foundation of the industrial revolution. The non-combustion resources such as nuclear power, solar power and geo-thermal energy are also used in these processes. The whole process of external combustion in the steam engines is the mechanical process. Water normally returns to the boiler and reach at high pressures. When this water is expanded through piston and turbines, then mechanical work is done. The reduced pressure steam is left to the atmosphere and condensed and pumped back to the boiler. The thermodynamic cycle, which is used in steam engines, is Rankine Cycle.

Discussion

The main components of steam engines are boiler or steam generator and motor unit. Motor unit is also referred as the steam engine. Some machinery has these two parts mounted together. There are also other components such as pumps which are also injectors, and supply water to the boiler, condensers for recirculation of water, and recovering of latent heat of vaporization, and super heaters, which raise the temperature of steam. The idea of using boiling water to produce steam was ancient. The ancient devices were not capable to produce power, but ideas were utilized and implanted before 300 years ago (Wiser, Wendell H., 2000).. There were also problems with installation and location. Today, modern steam engines are installed and used in each industry for several purposes. Transportation is also carried out on steam boats, and there are double steam boat engines in various boats, which increase the efficiency of the boats.

The source of heat which is used to boil the water can be derived from various means. The most common sources are combustible materials with proper supply of air in closed spaces such as combustion chamber and firebox. In some cases, heat sources are the nuclear reactor and geothermal energy. Boilers run on low pressures. They produce steam with high pressure. The purpose of the boiler is to provide heat in order to produce steam. They are the low pressure vessels which causes the water to boil. There are also mechanisms to transfer the heat to water. There are two most common methods of transferring the heat to the water:

In water tube boiler, water is run through several tubes, which are surrounded by various hot gases. They are more common today. The water runs through the track of tube.

In Fire tube boiler, water is filled partially below the vessel and the hot gases flow from above area. This boiler invented around 1800s. It mainly consists a tank with perforated pipes. The hot gases are supplied by means of wood and coal in order to ...