Systems and methods for determining the quantity of a combustion product in a vehicle exhaust

摘要

Exhaust after treatment systems for internal combustion engine powered vehicles are provided. One system includes logic in the form of one or more routines implemented by one or more of the system's components for determining the quantity of NO2 present in the exhaust that exits an oxidation catalyst, such as a diesel oxidation catalyst (DOC), without the use of an NO2 sensor. Results from such a determination may then be used to estimate the amount of soot present in the particulate filter. This estimated value of soot present in the particulate filter can then be subsequently used to determine when the particulate filter should be actively regenerated.

主权项

1. A system for determining an amount of NO2 exiting an oxidation catalyst of an exhaust after treatment system, comprising:
a space velocity generator configured to generate the space velocity of the oxidation catalyst as a function of oxygen concentration present in the exhaust entering the oxidation catalyst; an NO2 equilibrium generator configured to generate a value indicative of the NO2 equilibrium of the exhaust; an NO2 equilibrium fraction generator configured to obtain an NO2 equilibrium fraction; and an NO2 exit generator configured to generate a value indicating the quantity of NO2 exiting the oxidation catalyst based on the value indicative of the NO2 equilibrium of the exhaust and the NO2 equilibrium fraction.