How a Modern Car Engine Works
Introduction
The internal combustion engine is a type of heat engine that uses the expansion of hot gases to create mechanical work. In a car engine, this work is used to turn the crankshaft, which in turn drives the wheels.
Modern car engines are typically four-stroke engines, which means that they complete four strokes for each cycle of operation. These strokes are:
- Intake stroke
- Compression stroke
- Power stroke
- Exhaust stroke
Intake Stroke
The intake stroke begins when the intake valve opens, allowing air and fuel to enter the cylinder. The piston moves down the cylinder, creating a vacuum that draws the air and fuel in.
Compression Stroke
Once the intake valve closes, the piston begins to move up the cylinder, compressing the air and fuel mixture. This compression increases the temperature and pressure of the mixture, making it more combustible.
Power Stroke
At the top of the compression stroke, the spark plug ignites the air and fuel mixture. This creates a rapid expansion of hot gases, which forces the piston down the cylinder. This is the power stroke, which is the only stroke that actually produces work.
Exhaust Stroke
After the power stroke, the exhaust valve opens, allowing the hot gases to escape from the cylinder. The piston moves up the cylinder, pushing the exhaust gases out through the exhaust valve.
The Valve Train
The valve train is the mechanism that opens and closes the intake and exhaust valves. It consists of a camshaft, which is a rotating shaft with lobes that push on the valves, and a set of rocker arms, which transfer the motion of the camshaft to the valves.
The Fuel System
The fuel system is responsible for delivering fuel to the engine. It consists of a fuel tank, a fuel pump, a fuel filter, and a fuel injector. The fuel pump draws fuel from the fuel tank and sends it to the fuel injector, which sprays the fuel into the cylinder.
The Ignition System
The ignition system is responsible for creating the spark that ignites the air and fuel mixture. It consists of a battery, a distributor, a coil, and a spark plug. The battery provides power to the distributor, which sends the power to the coil. The coil creates a high-voltage spark, which is sent to the spark plug. The spark plug ignites the air and fuel mixture.
Conclusion
The modern car engine is a complex machine that converts the chemical energy stored in gasoline into mechanical work. This work is used to turn the wheels of the car, which allows us to travel from one place to another.
