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A predictive technique aimed at investigating the behaviour of intake and exhaust systems of internal combustion engine and at evaluating their influence on engine breathing and radiated noise is herewith presented. Such a technique is based on coupling a time domain gas dynamic model (composed of zero-dimensional, one-dimensional and three-dimensional methods) with a frequency domain linear acoustic analysis (transfer matrix method); thus a realistic prediction of complete engine systems is realised by adopting in each region the most appropriate method, according to the main features of the phenomena involved. The whole procedure has been applied to the intake system of an automotive engine and the results regarding different operative conditions are presented.

Concerns about the harmful exhaust emissions of internal combustion engines have imposed the employment of aftertreatment devices to reduce their impacts both on health and environment. System modeling of engine and aftertreatment devices is required not only to provide an accurate assessment of the engine and aftertreatment devices performances as single elements but also to quantify the complex interaction of these components from a thermo fluid perspective. The work focuses on development of a model capable of predicting temporal and spatial evolution of thermo-fluid quantities and chemical species in a diesel oxidation catalyst (DOC). The developed model allows to investigate the influence of thermal characteristics and gas composition on the evolution of the phenomena occurring in the device which deeply reflect on the particulate filter behavior during regeneration phase.

The current work presents the results of an investigation on the impact of renewable fuels on the combustion and emissions of a turbocharged compression-ignition internal combustion engine. An experimental study was undertaken and the engine settings were not modified to account for the fuel's chemical and physical properties, to analyze the performance of the fuel as a potential drop-in alternative fuel. Three fuels were tested: mineral diesel, a blend of it with waste cooking oil biodiesel and a hydrogenated diesel. The analysis of the emissions at engine exhaust highlights that hydrogenated fuel allows to reduce CO, total hydrocarbon emissions, particulate matter and NOx.