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Spiraling manufacturing costs for exhaust-gas treatment and tougher legislative requirements are good reasons for seeking new approaches to reach the ever-increasing emission-targets. Because of the strong correlation between technical feasibility and related costs, it is necessary not only to reach engineering targets but also achieve them at an acceptable cost. One decisive step in this regard is the so-called ‘Exhaust-Gas Management (EGM)’ strategy. The basic idea of EGM is an integrated optimization process of the complete engine periphery by evaluating the technical benefit and its cost. In the past the OEM has carried out this job as a rule, but a new form of EGM has since been defined through direct collaboration between engine periphery suppliers. In this paper the details of the new form of EGM and its benefits will be presented. This includes the steps involved in modifying the exhaust system and catalytic converter design, new ECU functions and calibration strategies.

Future catalyst systems need to be highly efficient in a limited packaging space. This normally leads to a design where the flow distribution, in front of the catalyst, is not perfectly uniform. Measurements on the flow test bench show that the implementation of perforated foils for the corrugated and flat foils has the capability to distribute the flow within the channels in the radial direction so that the maximum of the given catalyst surface is of use, even under very poor uniformity indices. Therefore a remarkable reduction in back pressure is measured. Emission results demonstrate cold start improvement due to reduced heat capacity. The use of LS - structured ( Longitudinal structured ) corrugated foils creates a high turbulence level within the single channels. The substrate lights-up earlier and the maximum conversion efficiency is reached more quickly.