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An innovative 0D predictive combustion model for the simulation of the HRR (heat release rate) in DI diesel engines was assessed and implemented in a 1D fluid-dynamic commercial code for the simulation of a Fiat heavy duty diesel engine equipped with a Variable Geometry Turbocharger system, in the frame of the CORE (CO2 reduction for long distance transport) Collaborative Project of the European Community, VII FP. The 0D combustion approach starts from the calculation of the injection rate profile on the basis of the injected fuel quantities and on the injection parameters, such as the start of injection and the energizing time, taking the injector opening and closure delays into account. The injection rate profile in turn allows the released chemical energy to be estimated. The approach assumes that HRR is proportional to the energy associated with the accumulated fuel mass in the combustion chamber.

Two different modifications of the baseline cylinder head configuration have been designed and experimentally tested on a MultiAir turbocharged gasoline engine, in order to address the issue of the poor in-cylinder turbulence levels which are typical of the Early-Intake-Valve-Closing (EIVC) strategies which are adopted in Variable Valve Actuation systems at part load to reduce pumping losses. The first layout promotes turbulence by increasing the tumble motion at low valve lifts, while the second one allows the addition of a swirl vortex to the main tumble structure. The aim for both designs was to achieve a proper flame propagation speed at both part and full load. The experimental activity was initially focused on the part load analysis under high dilution of the mixture with internal EGR, which can allow significant further reductions in terms of pumping losses but, on the other hand, tends to adversely affect combustion stability and to increase cycle-to-cycle variations.

The heating and cooling systems are an important issue in the development of fully electric vehicles (FEVs). On the contrary to vehicles with thermal engines, in FEVs there is almost no waste heat available for the heating of the cabin or for the window de-icing and defogging. The cooling of the cabin also demands a large amount of energy. Due to the high power consumption, the heating and cooling of FEVs is a compromise between thermal comfort and vehicle range. The aim of this work is to present the European project ICE (2010-2014) [1] which focuses on the development of an efficient air-conditioning and heating system based on a magneto-caloric heat pump and on a new system architecture to fulfill the thermal comfort requirements of an electric minibus. The system will be installed and demonstrated in a Daily Electric Mini-bus from IVECO-ALTRA.

Merging the fuel efficiency of diesel combustion with the use of renewable bio-fuels presents an attractive way towards an environmentally sustainable road transportation. But the introduction of bio-fuels have an impact on emission parameters as well as on engine and emissions after-treatment components performance and durability. This paper relates to the evaluation of the bio-fuel influence on particulate matter characteristics produced by a diesel engine and on DPF behavior during active and passive regeneration phases. The study was based on an EN590 compatible diesel fuel commercially available (B7), an EN14214 FAME biodiesel (B100) and their blend (B20). A direct injection single cylinder diesel engine was adopted for the experimental activity. Active regeneration phase was carried out via fuel vaporizer upstream oxidation catalyst. Results showed the particulate production rate was inversely proportional to fuel biodiesel content.