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A computational one-dimensional model of a solenoid operated common-rail ballistic injector has been performed and implemented in the AMESim software. A complete characterization of the different elements that comprise the system has been carried out in order to describe its behaviour. The model has been validated against mass flow rate experimental data along a wide range of engine-like operating conditions by varying the injection pressure, energizing time and injection temperature. The setup of the experimental facility is also described in the paper, with special attention to the injection temperature control. Results made it possible to quantify the influence of this injection temperature on the dynamic behaviour of such kind of injectors, where the needle lift is not limited and thus the viscous friction is deemed to be important on both the opening and closure stages of the injection event.

Experimental visualization of current gasoline direct injection (GDi) systems are even more complicated especially due to the proximity of spray plumes and the interaction between them. Computational simulations may provide additional information to understand the complex phenomena taking place during the injection process. Nozzle flow simulations with a Volume-of-Fluid (VOF) approach can be used not only to analyze the flow inside the nozzle, but also the first 2-5 mm of the spray. A methodology to obtain plume direction and spray angle from the simulations is presented. Results are compared to experimental data available in the literature. It is shown that plume direction is well captured by the model, whilst the uncertainty of the spray angle measurements does not allow to clearly validate the developed methodology.