Distributed control of selective catalytic reduction systems

摘要

Methods and systems are provided for modeling a reductant temperature and storage distribution of a SCR catalyst axially and radially. In one example, a method may include modeling an expected distribution of stored reductant among a plurality of axial zones and a plurality of radial zones of an SCR catalyst arranged in an engine exhaust passage and comparing the expected distribution with a reductant storage setpoint of each zone to adjust radial and axial storage locations.

主权项

1. A vehicle exhaust emission control system, comprising:
an SCR catalyst arranged in an engine exhaust passage downstream of a reductant injector; a controller comprising a processor and a non-transitory, computer-readable medium storing instructions executable by the processor to:
divide an embedded virtual model of an SCR catalyst stored in non-transitory memory of the controller into a plurality of radial zones;determine a reductant storage setpoint for each zone based on a volume and estimated temperature of the zone; andadjust a radial distribution of reductant in the SCR catalyst, based on a comparison of a current level of reductant stored in each zone with the reductant storage setpoint for that zone, by adjusting a spray pattern of reductant injected upstream of the SCR catalyst.