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Four Stroke Engines. How does a canon work?. Engine Operation. Gasoline & diesel engines convert chemical energy into mechanical energy. A Stroke…. When the piston moves from TDC to BDC, or vice-versa TDC: Top Dead Center BDC: Bottom Dead Center
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Four Stroke Engines How does a canon work?
Engine Operation • Gasoline & diesel engines convert chemical energy into mechanical energy
A Stroke… • When the piston moves from TDC to BDC, or vice-versa • TDC: Top Dead Center • BDC: Bottom Dead Center • Gasoline and diesel engines have to go through 4 strokes to create power to move the car
1st stroke: Intake stroke • the intake valve opens • the piston moves down
Intake Stroke Continued… • As the piston moves down the cylinder… • a mixture of gas and air enters the cylinder • this mixture is 15 parts air to 1 part gas (15:1 air – fuel ratio) • the air & fuel is mixed & delivered by the fuel system – either a carburetor or fuel injection system
2nd Stroke: Compression Stroke • Intake valve closes • Piston moves up the cylinder • When the piston reaches the top of the cylinder, the air & fuel has been squeezed to 150psi
3rd Stroke: Power Stroke • a spark created by the ignition system, jumps the gap at the spark plug & ignites the air/fuel mixture • This causes the burning gases to expand and drive the piston down the cylinder
4th Stroke: Exhaust Stroke • Once the piston reaches the bottom of the cylinder from the power stroke… • The exhaust valve opens • The piston moves up • The burnt gases are pushed out of the cylinder
Then what happens? • After the exhaust stroke, the piston begins moving down on another intake stroke, continually repeating the 4 strokes
Lets watch one… http://auto.howstuffworks.com/engine1.htm