Computational Model for Simulation of Diesel Injection Systems

Injection rate shaping is a powerful tool to control the combustion process and pollutants emission in DI Diesel engine. Recently, new injection systems that allow a more complete rate control have been developed.

This paper presents a model to simulate the hydrodynamics of these injection systems with two main objectives:

• To determine the influence of the different injection system geometrical parameters and to explore different configurations to optimise the injection rate shape.
• To determine the origin of the pressure perturbations that may appear in the system, due for example to interactions between injectors, and to quantify them.

This model has been developed with a modular approach that allows the simulation of very different injection system arrangements: classical pump-line-injector systems, common-rail system, and others. The paper describes:

• The model structure and the physical hypotheses compared with those of the bibliography.
• The methodology to characterise experimentally the main elements of the system.
• The methodology to adjust and validate the model with experimental data.