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Usually, the activation of DPF regeneration strategies is based on the estimation of the total particulate mass collected in the filter by means of the backpressure measure; no information concerning soot deposition profile on porous media is considered. In this paper, a numerical procedure is used to investigate the influence of soot profile on overheating during the regeneration process inside a commercial Diesel Particulate Filter. At first, the soot deposition profile, identified by a low number of parameters, is computed basing on the engine operative conditions. Then, the regeneration process is simulated. In this way, not only the amount of the total accumulated mass is taken into account, but the role of the shape of soot profile is accounted for. This allows to evaluate the correlation between the shape of collected particles layer and possible local overheating phenomena, which are very important to avoid critical thermal-structural stresses.

The performances of high pressure fuel-injection systems and their effects on diesel engine combustion are strongly influenced by the injector characteristics and the set up of the whole equipment control system. High-pressure system based on the common-rail architecture allows a multi-stage injection, which is of paramount importance in controlling combustion noise, fuel consumption, operation roughness and exhaust pollutant emissions. Common rail fuel injection equipment for automotive diesel engine, together with its control system have been analysed by using AMESim environment; both standard library elements and self-developed sub-models have been adopted. At first the different components have been considered one by one; in this way the behaviour of high pressure pump (radial-jet), pressure regulator, rail, injectors, system control (e. c. u.) has been investigated; the results have been compared with experimental measurements.