Reductant storage sensing system and method
AssigneeFord Global Technologies, LLC
InventorsDavid John Kubinski, Devesh Upadhyay
Life of this patent
Estimating the term…
Abstract
A catalyst supported on a substrate includes a heater embedded in a sub-region of the substrate to heat a local region of the catalyst. The amount of ammonia stored on the catalyst may be determined and controlled through conductivity measurements in the locally heated portion of the system described.
Claims13
A method of sensing operation of an SCR engine exhaust treatment device having base-metal-zeolite supported on a substrate, comprising:
- increasing temperature of a sub-region of the substrate;
- monitoring a change by sensing a conductivity of the base-metal-zeolite local to the sub-region;
- and
- outputting information based on said monitored change including correlating the change to an amount of stored ammonia in the base-metal-zeolite local to the sub-region.
A method of controlling engine operation, an engine having an SCR emission control device coupled in an engine exhaust, comprising:
- estimating an amount of ammonia stored in the SCR emission control device based on an operating condition by locally increasing temperature of a sub-region of the device, the temperature increased by supplying heat, wherein an amount of heat supplied is varied with operating parameters;
- measuring ammonia storage in the sub-region of the device and correlating said measure to an amount of ammonia stored throughout the SCR emission control device;
- and
- adjusting an amount of reductant injection into the exhaust based on said estimated and measured amounts.
A method of sensing operation of an SCR engine exhaust treatment device having a base-metal-zeolite supported on a substrate, comprising:
- increasing temperature of a sub-region of the substrate to substantially remove reductant stored on the base-metal-zeolite local to the sub-region, without removing ammonia stored in a remaining region of the base-metal-zeolite;
- monitoring a change in conductivity of the base-metal-zeolite local to the sub-region;
- and
- outputting information based on said monitored conductivity change.
Dependencies are inferred from the claim text.