F2010B032
Application of Increased Power Density for Future Diesel Engines - a Requirement for Downsized Powertrains
Regulated emissions, CO2-values, comfort, good driveability, high reliability and costs, this is the main frame for all future powertrain developments. In this frame, the diesel powertrain faces several challenges in order to fulfil the different future emission legislations while keeping the engine efficiency and in consequence the fuel consumption benefit.
One widely discussed approach for fuel consumption improvement within passenger car applications is to incorporate the downsizing effect. Certain publications have already discussed strategies for diesel engines with reduced capacity. The correlating impact on fuel consumption is therefore well-known. To maintain the high full-load performance of a diesel powertrain, an increase of the specific power has to be considered when facing future downsizing concepts. In this context, this publication deals with the further potential of increasing the specific power for HSDI diesel engines and the resulting consequences for the engine-out emission behaviour.
In order to increase the power density of a self-ignition engine different approaches are thinkable. While benefiting from an improved turbo charger design an optimized boost strategy can be developed. Furthermore, the layout of the injection system can be optimized for high full load performance. In detail, this includes investigations of different nozzles specifications with increasing hydrodynamic flow rate for improved full load performance while maintaining acceptable part load emission behaviour and fuel economy on superior level.
In addition to that, by means of cycle simulations, a trade-off between full load performance dependent on the specific power output and the part load emission behaviour will be analysed for future emission legislations. The shown results are based on single cylinder measurements and test cycle simulations.
This abstract is supplemented by a PDF, which can be viewed here.