INTERNAL COMBUSTION ENGINES AND STEAM ENGINES

THE STEAM ENGINE

Steam Engine Basic Information

• Thomas Savery an English military engineer patented the first crude steam engine

• He had been working on solving the problem of pumping water out of coal mines, his machine consisted of a closed vessel filled with water into which steam under pressure was introduced.

How The Steam Engine Works• The valve allows high-pressure steam to act

alternately on both faces of the piston• The slide valve is in charge of letting the high-

pressure steam into either side of the cylinder. The control rod for the valve is usually hooked into a linkage attached to the cross-head, so that the motion of the cross-head slides the valve as well.

• On a steam locomotive, this linkage also allows the engineer to put the train into reverse.

• The exhaust steam simply vents out into the air. This fact explains two things about steam locomotives:

• •It explains why they have to take on water at the station -- the water is constantly being lost through the steam exhaust. It explains where the "choo-choo" sound comes from. When the valve opens the cylinder to release its steam exhaust. The steam escapes under a great deal of pressure and makes a "choo!" sound as it exits. When the train is first starting, the piston is moving very slowly, but then as the train starts rolling the piston gains speed.

Different Types of Steam Engines

• Simple expansion-one cylinder.• Oscillating cylinder steam engines- simple expansion

steam engine which does not require valves• Compound Engine-steam enters the cylinder at high

temperature and leaves at low temperature.• Multiple Expansion Engine-More than one cylinder.• Uniflow Engine- provides an additional port

uncovered by the piston at the end of each stroke making the steam flow only in one direction.

THE FIRST STEAM ENGINE

• YouTube - Steam Engines - The Aoelipile

INTERNAL COMBUSTION ENGINES

Basic Information about Internal Combustion Engines

• The first person to experiment with an internal-combustion engine was a Dutch physicist Christian Huygens in about 1680. But no effective gasoline-powered engine was developed until 1859.

• The French engineer J. J. Étienne Lenoir built a double-acting, spark-ignition engine that could be operated continuously.

• The first successful 4 stroke engine was known as the “otto cycle”

How the Internal Combustion Engine works

• 1.The piston starts at the top then the intake valve opens, and the piston moves down to let the engine take in a cylinder-full of air and gasoline. This is the intake stroke. Only the tiniest drop of gasoline needs to be mixed into the air for this to work.

• Then the piston moves back up to compress this fuel/air mixture. Compression makes the explosion more powerful.

• When the piston reaches the top of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes, driving the piston down.

• Once the piston hits the bottom of its stroke, the exhaust valve opens and the exhaust leaves the cylinder to go out the tailpipe.

Different Types of Internal Combustion Engines

• 2 Stroke Cycle• 4 Stroke Cycle• 6 Stroke Engine• Atkinson Cycle• Wankel Engine• Brayton Cycle(Gas turbine, Jet Engine)

The First Combustion Engine

• HowStuffWorks Videos "The Stuff of Genius: Internal Combustion Engine"