Establishment of a Real-Time Simulation of a Marine High-Pressure Common Rail System

Abstract

In this paper, the high-pressure common rail system of the marine diesel engine is taken as case study to establish a real-time simulation model of the high-pressure common rail system that can be used as the controlled object of the control system. On the premise of ensuring accuracy, the real-time simulation should also respond quickly to instructions issued by the control system. The development of the real-time simulation is based on the modular modeling method, and the high-pressure common rail system is divided into submodels, including the high-pressure oil pump, common rail tube, injector, and mass conversion. The submodels are built using the “surrogate model” method, which is mainly composed of MAP data and empirical formulas. The data used to establish the real-time simulation are not only from the empirical research into the high-pressure common rail system, but also from simulations of the high-pressure common rail system undertaken in AEMSim. The data obtained from this real-time simulation were compared with the experimental data to verify the model. The error in fuel injection quality is less than 5%, under different pressures and injection durations. In order to carry out dynamic verification, the PID control strategy, the model-based control strategy, and the established real-time simulation are all closed-loop tested. The results show that the developed real-time simulation can simulate the rail pressure wave caused by cyclic injection according to the control signal, and can feedback the control effect of different control strategies. Through verification, it is clear that the real-time simulation of the high-pressure common rail system can depict the rail pressure fluctuation caused by each cycle of fuel injection, while ensuring the accuracy and responsiveness of the simulation, which provides the ideal conditions for the study of a rail pressure control strategy.

Numerical Analysis of the Structural and Flow Rate Characteristics of the Fuel Injection Pump in a Marine Diesel Engine

“…Their reports create scratches on the moving surfaces and accelerate sticking or wear in reciprocating fuel pumps [2,5,6]. A marine high-pressure common rail system using MAP data and empirical calculations in AMESim was modeled by Wang et al [8]. Their results showed the variation in rail pressure induced by each fuel injection cycle.…”

Research on the influential factors related to the fuel leakage rate in the plunger-sleeve clearance of high pressure common rail system

“…High pressure common rail system has the characteristics of high injection pressure and precise control of injection timing and cycle injection quantity, which is key to improving the dynamic performance, ensuring energy efficiency, and reducing emissions in modern diesel engines. [1][2][3] With stricter mandatory emission regulations for diesel engines, improving the fuel pressure of common rail systems to accelerate oil droplet atomization and adopting multiple injection strategies to optimize in-cylinder combustion are effective means to achieve higher thermal efficiency and lower emissions of diesel engines. [4][5][6] The plunger-sleeve in the injector and the plungersleeve in the high-pressure fuel pump are important precision machined parts of the high pressure common rail injection system.…”