New Diesel New Diesel – Effizienzsteigerung von Nutzfahrzeug-Dieselmotoren unter Einhaltung der zukünftigen Emissionsgesetzgebung

The global overland freight traffic is dominated by diesel engines. The economical transport of goods therefore significantly depends on the future development of fuel efficient diesel engines in a power range of 250 kW to 500 kW.

On the other hand more and more restrictive emission limits require an exhaust aftertreatment with increasing complexity. The trade-off between emissions and fuel efficient engine operation requires a global development approach that covers the whole engine process and includes modern simulation- and testing-tools.

A comprehensive numerical model was created, including a detailed engine model based on physical principles and a model of the exhaust aftertreatment that enabled the prediction of the thermal behaviour and the reduction of the nitric oxides in the SCR-catalyst based on the reaction kinetics. The verification of the models was carried out with stationary and transient test results from the engine test bench.

For the system optimization a reduction of the model was carried out by means of neural networks. A significant reduction of the simulation times close to real-time was achieved. It could be shown with the Design-of-Experiments (DoE) method that the engine application enabled an optimal engine operation in terms of fuel efficiency.  Further potentials to reduce the nitric oxide emissions without influencing the fuel consumption by improving the design of the exhaust system could be shown with this method.