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An approach for model-based control strategy design for diesel hybrid drive-trains has been developed, permitting the reduction of fuel consumption as well as of exhaust gas emissions. The control strategy consists of four core-functions: the SOC-management, the operation mode determination, the gear selection, and the thermal monitoring. Based on those different interpretations, a control strategy can be designed that leads to great reductions in fuel consumption or alternatively to a mentionable decline of nitrous oxides. In this trade-off, both aims can not be optimized at a time. Though, the strategy to be used is a compromise, designs for control strategies are possible that reduce both for a significant amount. Extending this control strategy by adding functions for transient behavior at start-up and load changes; phlegmatization enables additional potentials for emission reduction.

Diesel engines face difficult challenges with respect to engine-out emissions, efficiency and power density as the legal requirements concerning emissions and fuel consumption are constantly increasing. In general, for a diesel engine to achieve low raw emissions a well-mixed fuel-air mixture, burning at low combustion temperatures, is necessary. Highly premixed diesel combustion is a feasible way to reduce the smoke emissions to very low levels compared to conventional diesel combustion. In order to reach both, very low NOX and soot emissions, high rates of cooled EGR are necessary. With high rates of cooled EGR the NOX formation can be suppressed almost completely. This paper investigates to what extent the trade-off between emissions, fuel consumption and power of a diesel engine can be resolved by highly premixed and low temperature diesel combustion using injection nozzles with reduced injection hole diameters and high pressure fuel injection.

In this paper it is set down how the luminosity of the pre-combustion inside an optically accessible direct injection common rail diesel engine is directly detected by super-sensitive detection technique consisting of an image intensified UV and VIS CCD camera with on-chip integration. During pre-combustion first a weak chemi-luminescence of hydrocarbon is observed which is followed in some cases by bright light emissions from soot. This investigation focuses on chemiluminescence. Due to the extremely weak light emissions the image intensifier was switched to maximum, the light emissions of usually 100 single engine cycles were summed up on the CCD chip at an exposure duration of two degrees crank angle for each cycle. Stoichiometric or lean pre-combustion can clearly be detected with this highly sensitive setup.