|Amazing Men and their Magical Machines||
The steam engine is similar to the Stirling cycle engine in so far as it is also a heat engine however this is where the similarity's end.
Unlike the Stirling engine steam is used as the working fluid and is not contained inside the engine. The steam leaves the engine through an exhaust which would never happen in a Stirling engine.
The steam engine became the best form of energy during the 18th centaury and was used for transport and as a power source for the great factory's which made the world what it is today.
The steam engine is still used to generate electricity for the modern world and it is run on a wide variety of fuels.
History of the Steam Engine
Steam engines have been for at least 2000 year's but it was only in the last couple of hundred years that these engines have been able to produce useable power. The steam engine provided the power which drove the industrial revolution. One of the greatest reason's it was able to do this was because it provided power to area's which could not use water wheels or windmills to produce the power needed.
The steam required to make a stem engine operate is created in the boiler. The fuel e.g. coal is fed into the furnace to produce enough heat to boil the water and produce stem. There are two ways in which this can be done.
The water can be in a large tank with a number of pipes flowing through it. These pipes are full of hot gasses on their way to the exhaust. These hot pipes heat the water to boiling and it leaves the boiler as steam and enters the engine. This can be dangerous as the entire tank is under pressure and there is the potential of an explosion. This configuration is shown below:
The alternative is to have the water flowing in the pipes instead of the hot gasses. The water flows through pipes which enter the furnace. The water is heated and leaves the furnace as steam which continues to the engine to produce work. This configuration is shown below:
The steam then enters the slide valve housing. This valve controls the flow of the working fluid into and out of the cylinder. It allows hot steam to flow in one side of the cylinder which pushes the piston along. This movement of the piston can be used for work. As the piston is moved along it pushes the cold steam through the slide valve and out the exhaust. This is shown in the figure below:
When the valve moves the steam flows in the opposite direction as shown in the figure below:
Every time the piston moves in or out it expels steam out through the exhaust which means that the engine needs to be regularly topped up with water as well as fuel.