Intake O2 Concentration Estimation in a Turbocharged Diesel Engine through NOE
Diesel engines with their embedded control systems are becoming more and more complex as the emission regulations tighten, especially concerning NOx pollutants. The combustion and emission formation processes in diesel engines are closely correlated to the intake manifold O2 concentration. Consequently, the performance of the main engine controllers can be improved significantly, if a model-based or sensor-based estimation of the intake O2 concentration is available in the ECU. The paper addresses the modeling of the intake manifold O2 concentration in a turbocharged diesel engine. Dynamic models, compared to generally employed steady state maps, capture the dynamic effects occurring over transients. It is right in the transient that the major deviations from the stationary maps are found. The dynamic model will positively affect the control system making it more effective.