What is the role of the piston in compressing the air-fuel mixture?

The piston plays a critical role in the internal combustion engine by compressing the air-fuel mixture within the cylinder. During the intake stroke, the piston moves downward, allowing the air-fuel mixture to enter the cylinder. As the piston then moves upward during the compression stroke, it decreases the volume of the mixture, effectively increasing its pressure and temperature. This compression is essential because it prepares the mixture for ignition, ensuring that it ignites efficiently and maximizes the power produced during the combustion process.

By compressing the mixture, the piston also enhances the thermal efficiency of the engine. A higher compression ratio generally leads to better fuel combustion and power output. Therefore, the function of the piston is integral for optimal engine performance, as it compresses the mixture before it is ignited, facilitating a more powerful and efficient combustion event.