What type of fuel injector is commonly used in diesel engines?

The commonly used type of fuel injector in diesel engines is the unit injector. This design integrates the fuel pump and injector into a single unit, which allows for precise control of the injection process. This precision is crucial for diesel engines, as they rely on the fuel being injected at high pressures to ensure proper atomization and combustion.

Unit injectors are advantageous because they operate independently for each cylinder, providing better performance and efficiency. Additionally, they can handle the higher pressures associated with diesel fuel injection compared to gasoline engines, which typically use different types of injectors.

In comparison, other types like common rail injectors are also prevalent in modern diesel engines, but the unit injector has been a traditional choice, especially in older designs or specific applications. Air-assisted injectors, primarily used in gasoline engines, and solid jerk injectors, which are less common in contemporary applications, do not align with the needs of diesel engine performance in the same way.