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Establishing a certain maintenance-free time period regarding modern diesel exhaust emission control systems is of major importance nowadays. One of the most serious problems Diesel Particulate Filter (DPF) manufacturers face concerning system's durability is the performance deterioration due to the filter aging because of the accumulation of the ash particles. The evaluation of the effect of the ash aging on the filter performance is a time and cost consuming task that slows down the process of manufacturing innovative filter structures and designs. In this work we present a methodology for producing filter samples aged by accumulating ash produced by the controlled pyrolysis of oil-fuel solutions. Such ash particles bear morphological (size) and compositional similarity to ash particles collected from engine aged DPFs. The ash particles obtained are compared to those from real engine operation.

Diesel Particulate Filters (DPFs) need to be periodically regenerated in order to achieve efficient and safe vehicle operation. Under typical diesel exhaust conditions, this invariably requires the raising of the exhaust gas temperature by active means, up to the point that particulate (soot) oxidation can be self-sustained in the filter. In the present work the development path of an advanced catalytic filter technology is presented. Full scale optimized Catalytic Diesel Particulate Filters (CDPFs) are tested in the exhaust of a light-duty modern diesel engine in line with a Diesel Oxidation Catalyst (DOC). The management of the DOC-CDPF emission control system is facilitated by a virtual soot sensor in order to ensure energy-efficient operation of the emission control system.

In this paper a fast DPF screening procedure is proposed using small-scale filter samples of different technologies in a well-controlled environment but under realistic engine exhaust conditions. The DPF samples are evaluated in a specially built Multi-Reactor Assembly (MRA) with respect to their flow resistance, filtration efficiency, soot loading behavior, soot oxidation behavior, as well as their ash induced ageing behavior.