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SuperGen is a Belt Integrated Starter Generator (B-ISG) combined with a novel electro-mechanical power split transmission system providing variable speed centrifugal supercharger capability, all in one compact package. This paper initially discusses the analysis of SuperGen application to a gasoline SUV in order to examine the BISG power and voltage mild hybrid functionality trade-off versus fuel consumption reduction on drive cycle. A significant engine down speeding was also applied based on the low speed torque enhancement afforded by SuperGen boosting capability, both transiently, and sustainably at steady state engine operation. This has been demonstrated and reported on the well-published Jaguar Land Rover (JLR) Ultraboost project.

This paper presents the summary of the development of a two-phase spray model of a hollow-cone fuel injector commonly applied to spray-guided, gasoline direct injection, (SGDI) engines. The model was simulated using the Ricardo VECTIS CFD code and takes into account the physical and chemical effects of oxygenated fuel blends (flexfuels). The characteristics of the fuel sprays at typical gasoline part-load conditions, identified in a parallel study, were of particular interest. An injection duration of 0.3 ms was chosen which represented a stratified charge, unthrottled, part-load operating condition in a spray guided GDI engine with a piezoelectric fuel injector and a fuel injection pressure of 200 bar gauge. In the first instance, the spray model was validated against data recorded in a constant volume spray chamber. Secondly, the robustness of the model was tested against data measured in an optically-accessed engine.

Compared to conventional homogeneous direct injection or port-fuel injected engines, the second generation, spray guided, direct injection engine (SGDI) has the potential for significantly improved fuel economy during part load stratified charge operation. Multiple fuel injection strategies can be utilised to increase the unthrottled operating range, leading to further improvements in fuel economy. However, careful optimisation of these strategies is essential to ensure that benefits are maintained whilst further minimising emissions within combustion stability limits and consumer driveability demands. The effects of multiple injection strategies upon fuel consumption, emissions and combustion stability were investigated in a single cylinder Ricardo Hydra engine with a spray guided combustion system. An outwardly opening piezoelectric actuated injector was employed. The fuel injection strategy utilised up to five injections per engine cycle.

Cosworth Technology has converted a prototype V6 Manifold Port Injected (MPI) gasoline engine to homogeneous charge Gasoline Direct Injection (GDI), whilst increasing rated power by over 16% despite higher inlet and exhaust pressure loss targets. This paper describes the development methods used to deliver the project in very short time scales, and includes details on the how five different GDI injectors were tested on a GDI slave engine, followed by results from further part and full load engine testing of the best injector configuration. In parallel with the GDI developments, 1-D cycle simulation in GT-Power was used in conjunction with engine dynamometer testing to develop hardware to meet performance targets, and details of the results of predicted and actual performance are included. Overviews of tools and techniques utilized to speed up this GDI application, such as GT-Power, CFD, DOE and hydraulic system simulation and rig testing are also presented.

An overview of work relating to the investigation of direct injection gasoline engines is presented. Comparisons between conventional port-injected and two separate gasoline direct injection combustion systems are drawn. The comparison is between two of the main alternative GDI systems currently under consideration, reverse tumble charge motion with high-pressure swirl-type fuel injector (RTGDI) and low-pressure air-assist direct injection (AAGDI). This comparison was carried out using a 444cc single cylinder research engine of Cosworth Technology design. Included in the discussion are the influence of GDI systems on volumetric efficiency and performance at full load and fuel efficiency and emissions at part load. Techniques to aid the development and calibration of GDI systems are discussed, including Moving Geometry CFD analysis and Design of Experiments (DOE).