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2009-09-13
Technical Paper
2009-24-0113
Daniel Alberer, Luigi del Re
Transient emission peaks have become an important fraction of the total emissions during the standardized test cycles for passenger car Diesel engines. This paper is concerned with their reduction, in particular for nitric oxides (NOx) and particulate matter (PM) emissions, by online optimization. It is based on a former work [1] in which alternative target quantities for engine control were proposed, namely in-cylinder oxygen concentrations before (O2,BC) and after combustion (O2,AC). A generic nonlinear optimization is applied to provide a systematic determination for the optimal trajectories of these oxygen target quantities during a transient torque maneuver. The proposed method was implemented on a dynamic engine test bed using a production passenger car Diesel engine for the objective function evaluation. Torque response could be maintained unchanged while NOx as well as PM emission peaks were reduced significantly.
2009-04-20
Journal Article
2009-01-0622
Daniel Alberer, Luigi del Re
Due to the advancements in passenger car Diesel engine design, the contribution of transient emission spikes has become an important fraction of the total emissions during the standardized test cycles, hence the interest of this work on dynamical engine operation, in particular on the improvement of NOX and PM emissions. This paper proposes to use a UEGO sensor (universal exhaust gas oxygen sensor) in the upstream of the turbine in combination with a Kalman filter to estimate the target quantities, namely in-cylinder oxygen concentration before and after combustion. This information is used to define the fuel injection as well as the values of the air path actuators. Test bench measurements with a production Diesel engine are presented, where the oxygen based approach is compared to the standard calibration during a fast load increase. It is shown that the torque response could be maintained while NOX as well as PM emission peaks were reduced significantly.
2005-09-11
Technical Paper
2005-24-063
Daniel Alberer, Luigi del Re, Stephan Winkler, Peter Langthaler
As a physical description of the emissions of a specific engine is seldom possible, we present here a method to design an online dynamic estimator for PM and NOx based on data. The design method is based on a systematic search of function candidates performed using genetic programming after data have been pre-treated in an adequate fashion. While data and a simple data pretreatment prove enough for NOx, some basic physical understanding is necessary to preset the method and obtain the required precision in the case of PM. The method has been applied for raw emissions of a production DI diesel engine and shows a remarkable prediction performance.
2007-04-16
Technical Paper
2007-01-0864
Markus Hirsch, Daniel Alberer, Luigi del Re, Clemens Schelhaas
Two-wheel vehicles are becoming continuously more important in Europe, but their spread is accompanied by an increase in security concerns due a number of reasons. These include stability problems during braking, and in particular curve braking, which is much more critical than in 4-wheel vehicles. These stability problems are strongly influenced by the behavior of the driver, in particular by his braking and steering activity. In this work we present a curve-safe ABS control, and analyze the role of the driver by a simulation model. It turns out that the demands on the driver in terms of stability control vary strongly with the braking behavior.
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