Abstract
Keywords - Gasoline Direct Injection Engine, High Pressure Fuel Pump, Flow Rate Control Solenoid Valve, Noise, Acoustics
Gasoline Direct Injection (DI) is a key-enabling technology for reduced fuel consumption and emissions, and increased engine power in spark ignition (SI) engines. This has led to a very rapid increase in deployment of DI engines, as car-makers develop downsized engines without compromises on performance. A key component of a DI system is the fuel pump, which must deliver fuel at much higher pressures than a conventional SI engine. For a DI pump, the fuel flow rate and the size, noise emission and electrical power consumption are conflicting requirements. This paper describes the development of a compact single-cylinder DI pump which achieves increased fuel flow rates while consuming decreased electrical power and generating less noise, compared to conventional DI pumps currently on the market. This is achieved by the introduction of a new concept for the flow rate control valve, in combination with integrated relief valve. This novel flow rate control valve is normally-closed, which makes it possible to generate high magnetic power at the valve opening position with less electrical energy. In addition, the flow rate control valve moves passively by the hydraulic forces, such that the impact noise at valve opening is reduced significantly.