WORKING PRINCIPLE OF INTERNAL COMBUSTION ENGINE

The working principle of an internal combustion engine is based on burning a mixture of fuel and air inside the combustion chamber to generate mechanical energy. The most common type is the 4-stroke engine, which includes four main stages:

1. Intake Stroke

The piston moves from Top Dead Center (TDC) to Bottom Dead Center (BDC).
The intake valve opens, and the exhaust valve closes.
Air and fuel mixture (gasoline/diesel) is drawn into the cylinder.

2. Compression Stroke

The piston moves from BDC to TDC.
Both intake and exhaust valves remain closed.
The air-fuel mixture is compressed, increasing pressure and temperature.

3. Power Stroke

When the piston reaches TDC, the spark plug ignites the mixture (gasoline engines) or the fuel self-ignites (diesel engines).
The explosion occurs, expanding the combustion gases and pushing the piston downward, generating mechanical power.
This is the only power-generating stroke.

4. Exhaust Stroke

The piston moves from BDC to TDC.
The exhaust valve opens, and the intake valve closes.
Burnt gases are expelled from the cylinder.

⛽ The cycle then repeats.

🎯 Quick Summary:
Intake → Draw air and fuel.
Compression → Compress the mixture.
Power → Combustion generates power.
Exhaust → Expel exhaust gases.