Suoraruiskutuksen

Suoraruiskutus, often referred to as direct injection, is a fuel delivery system used in internal combustion engines. In this system, fuel is injected directly into the combustion chamber rather than into the intake manifold or cylinder head ports as in older port fuel injection systems. This direct delivery allows for more precise control over the fuel-air mixture and combustion process.

The primary advantage of direct injection is improved fuel efficiency and reduced emissions. By injecting fuel directly, engineers can achieve a more stratified or homogeneous mixture within the cylinder, leading to more complete combustion and less wasted fuel. This precision also allows for higher compression ratios, further enhancing efficiency. Furthermore, the cooling effect of the evaporating fuel inside the combustion chamber can help suppress knocking, enabling more aggressive ignition timing.

Direct injection systems typically employ high-pressure fuel pumps and injectors capable of withstanding the extreme conditions within the combustion chamber. The injectors are strategically positioned to spray fuel at the optimal moment during the intake or compression stroke. Different strategies exist, such as GDI (Gasoline Direct Injection) for gasoline engines and common rail direct injection for diesel engines, each with its specific implementation and benefits. While offering significant advantages, direct injection systems can be more complex and costly to manufacture and repair compared to port injection.