Procedure and Design of Exhaust Systems to Fulfill all Emission Limits During Real Driving Conditions: "In Use Conformity"

Authors

Dr. S. J. Ahlers, Dipl.-Ing. R. Brück, Dipl.-Ing. T. Cartus, Dipl.-Ing. H. Stock, Continental Emitec GmbH, Lohmar; Dr. O. Maiwald, Continental Automotive GmbH, Regensburg

Year

2018

Print Info

Fortschritt-Berichte VDI, Series 12, No 807

Summary

Current discussions on the future of the combustion engine and in particular on the future of diesel engines lead inevitably to the development of “emission-safe” concepts. For this, the systems must be capable of compensating for the influence of the driver, traffic, fuel and the ambient conditions. At development stage, however, testing the great number of variables at an acceptable cost and in an acceptable time frame can only be achieved with difficulty. For this reason, a procedure was established of developing a test cycle out of the numerous vehicle tests, which reflects “worst case” driving conditions. With the aid of specially developed algorithms, it is possible to adapt this test to various drive concepts and engine sizes without running fresh vehicle tests. Naturally, further validations to establish general applicability will be necessary. In addition, an evaluation tool, which aids developers in the design of the exhaust-gas aftertreatment system, was developed to support analysis of emission measurements. However, the tool has its limitations, which means that it is necessary to intervene actively by means of engine management. This produces an extremely clean total concept which prevents “misuse” at the same time. Finally, generic examples were used to illustrate the possibilities of improving exhaust-gas aftertreatment and a potential ultimate example was theoretically worked out.