Abstract
When developing the system, the company sought to minimize changes to the existing engine design, which largely determined the chosen layout. Furthermore, when developing the fuel system, it was necessary to take into account the protective effects of numerous patents, which influenced a number of design decisions. Common rail fuel systems for diesel engines in high-speed vehicles vary significantly in circuit design and the structure of individual components. Therefore, the most common design variations of these systems are discussed below. The fuel system design largely depends on the engine cylinder volume. The low-pressure fuel pump supplies the required fuel to the high-pressure fuel pump. A pressure-reducing valve maintains a constant pressure at the inlet of the high-pressure fuel pump section, located in the housing. As the name suggests, high-pressure fuel pumps are designed to create high pressure in the fuel line, which must always be significantly higher than the pressure in the engine cylinder, which is necessary for the normal operation of all similar fuel injection systems. To ensure stable operation of the high-pressure sections of diesel engines and effective lubrication of their supporting structures, a supply pressure of 0.5–0.8 MPa is required.