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Car manufacturers today face the dual challenge of remaining competitive while addressing the impact of automotive emissions on the environment. With the emergence of advanced combustion modes, and the growing importance of downsizing along with the rising complexity of after treatment devices, fuel variability is now one of the major constraints that must be addressed for the automotive industry to move forward. Accounting for variability in the properties of commercial fuel blends leads to significant improvements, such as allowing gasoline engine operation closer to the knock limit, adjusting engine tuning based on the fuel engine combination to ensure a better match between performance, emissions and consumption as measured on validation proto fuels and what is generated under real driving conditions. The evaluation of fuel impact on the engine performance showed the limitations of characterizing the fuel variability from the conventional properties.

This paper presents the main properties of a SiC diesel particulate filter bonded with specific ceramic oxides at a markedly lower sintering temperature than normal pure SiC DPF. The elasticity of the bond has been studied to have a good behavior to thermal shock permitting a larger cross section element and a reduction of the number of cement joints in the final monolith. That new product, manufactured at present is composed of seven square elements. Endurance tests have been carried out by laboratory bench testing in two commercial automobile diesel engines. The DPF pore size has been adjusted so that it may be catalyzed or impregnated.

The reduction of particulate emissions from Diesel engines is a key issue to meet future emission standards. Particulate traps represent an attractive solution to the problem of this source of pollution. However, they have the disadvantage of requiring periodic and safe regeneration to release exhaust back pressure and to recover filtration efficiency. Natural regeneration of the particulate filter may occur. Nevertheless, with light-duty vehicles and their low level of exhaust gas temperature, it may be necessary to facilitate or force the regeneration. The objective of this work is to give an overview of the possibilities offered by the engine management system to increase significantly exhaust gas temperatures. Thus, different engine tunes, through injection timing, boost pressure or EGR rate, may be sufficient to ensure safe regeneration of the trap.