bei Google ScholarTitelangaben
Ritter, Thomas ; Seibel, Maximilian ; Hofmann, Frank ; Weibel, Michel ; Moos, Ralf:
Simulation of a NOx sensor for model-based control of exhaust aftertreatment systems.
2018
Veranstaltung: CAPOC11 - 11th International Congress on Catalysis and Automotive Pollution Control
, Oct. 29 - 31, 2018
, Brussels, Belgium.
(Veranstaltungsbeitrag: Kongress/Konferenz/Symposium/Tagung
,
Poster
)
Abstract
Optimal control of the exhaust aftertreatment components is an important aspect for minimizing pollutants. Nitrogen oxides are therefore monitored using amperometric gas sensors. However, they show marked crosssensitivities to ammonia, which can be disadvantageous, e.g., if they are applied in NH3 selective catalytic reduction systems. In this study, a model that simulates the operation of an NOx sensor is developed. The three oxygen pumping cells and the upstream diffusion barriers were implemented in a 1D geometry, with the relevant electrode reactions taking place over its length. The diffusion barriers were calculated quasistationary. The dynamics of incoming gas components as a function of the exhaust mass flow were integrated with a first order LTI system. The problem was calculated using the convection-diffusion equation. The reaction kinetics were determined on the basis of stationary measurements in laboratory atmosphere, whereby initially only the reaction with respect to NO and NO2 was considered. Then, the cross-sensitivities to oxygen, water and ammonia were examined. The developed data set could then be used for transient boundary conditions. The simulated and the measured sensor signals in the case of engine test bench conditions with real driving cycles agree very well.