Heterogeneous Combustion Explained

Heterogeneous combustion is a process where the fuel and air are not uniformly mixed before ignition occurs. This leads to variations in the fuel-air ratio within the combustion chamber.

Engine Combustion Mechanisms

Different engine types utilize distinct combustion strategies:

• Compression Ignition (CI) Engines: Commonly known as diesel engines, CI engines inject fuel directly into the cylinder containing hot, highly compressed air. The mixing of fuel and air happens simultaneously as combustion initiates, resulting in localized regions with varying fuel concentrations. This inherently creates a heterogeneous mixture during combustion.
• Spark Ignition (SI) Engines: Typically used in gasoline engines, SI engines rely on a spark plug to ignite a fuel-air mixture that is usually pre-mixed and relatively homogeneous (uniform) before ignition.

Association with Heterogeneous Combustion

Based on the combustion process, Compression Ignition engines are directly associated with heterogeneous combustion because the fuel injection and mixing occur in an uneven manner during the combustion event.