To meet the increasingly stringent emission regulations, as well as marine diesel engines to improve fuel economy, reliability and flexibility of operation, the control of marine diesel engine made increasing demands. The key to improve the performance and reduce marine diesel engine emissions is to improve the combustion process in which fuel system plays a very important role, so the common rail fuel injection technology to become one of the direction of marine diesel engine fuel system development. And by diesel common rail fuel system simulation can solve the common rail system R & D in many of the technical problems, the simulation model calculations can guide the bench, may also be applied to the development of design simulator can be used as crew training platform, but also in the research and design of the diesel fuel in the common rail system can shorten the cycle time, save a lot of manpower, material and financial resources.

 This paper focuses on marine diesel engine common rail system to expand simulation. It focuses on Sulzer RT-flex common-rail diesel systems, which includes the fuel system, starting air systems and exhaust valve drive system, and introduces the main components of the common rail fuel system (fuel supply unit, common rail injection unit and the control unit ) and Wartsila diesel Engine control systems (WECS-9500 control system) works, as well as the composition associated with the diesel engine, the cylinder control.

Using the basic principles of fluid mechanics of the mathematical model of the common rail fuel system, including the calculation of the fuel rail pressure, fuel injection control valve (including a control valve motion equation and the equation of motion of the piston oil and fuel injection quantity), the high-pressure fuel pump pump , the amount of fuel injection nozzles and injectors.

 Use of Matlab / Simulink 7.0 Modeling and Simulation Software for Common Rail Diesel Engine Fuel system modular modeling, simulation model including fuel rail modules, fuel rail valve module, injector module, injection timing and injection control module module. Wherein the cylinder compression pressure, injection timing and fuel injection quantity as boundary conditions, linear interpolation parameters under different conditions by the table lookup method.

Through simulated conditions of a typical common rail system fuel rail pressure curve and the nozzle chamber pressure curve, reflecting the different conditions fluctuations in rail pressure, injection timing and injection duration, and with the fuel rail pressure through the simulation work , common rail fuel injection quantity and volume on the rail pressure fluctuations.

Through simulation of the common rail fuel system to obtain a more precise common rail fuel system model used for simulation, optimization design, development, and crew training simulator has a certain reference value.