Direct injection fuel system utilizing water hammer effect

摘要

A method is described for operating a fuel system during start up, the system utilizing gasoline direct injection for an internal combustion engine including a first pump and second pump, an electromechanical valve, and a check valve fluidly coupled downstream of the first pump. The fuel system further includes a fuel rail downstream of the check valve and direct fuel injectors coupled to the engine. The method includes generating a flow of fuel in the fuel system via the first pump during an engine start before ignition of the engine; actuating the valve during the fuel flow to generate a pressure wave that travels through the fuel system past the check valve; and injecting fuel via the direct fuel injectors at an increased pressure generated by the pressure wave and held in the fuel rail via the check valve.