A Study of Rail Pressure Variation for Various Fuel Injectors on a Simple Rail Design Over the Engine Operation Range

The pressure variation in the fuel supply system due to injector firing and other system inputs has been widely discussed in SI engine technology. It can affect engine calibration, performance and compliance to emission standards through its effect on fuel distribution between the cylinders. It can also generate mechanical noise and vibration that may be annoying to the occupants of the vehicle. Much discussion has focused both on modeling this condition and on ways to alleviate the problem through the use of damping devices. This study presents topographical maps of fuel pressure variation over the engine operation range for a simple non-damped rail with a variety of injectors. The injectors tested are manufactured by different companies and have different flow rates.