Abstract: An electronic control system is adapted to control a system including an internal combustion engine and an exhaust aftertreatment system including an SCR catalyst. The electronic control system provides a first dynamically determined weighting factor in response to performing a selected one of a plurality of calculations, determines an operating mode of the engine in response to an engine load and an engine speed, selects one of a plurality of inputs in response to the operating mode of the engine to provide an interpolation weighting factor, the plurality of inputs including the first dynamically determined weighting factor and one or more predetermined weighting factors, utilizes the interpolation weighting factor to interpolate between a first set of combustion control data and a second set of combustion control data to determine a set of combustion control values, and controls operation of the engine using the set of combustion control values.

Abstract: An electronic control system is adapted to control a system including an internal combustion engine and an exhaust aftertreatment system including an SCR catalyst. The electronic control system provides a first dynamically determined weighting factor in response to performing a selected one of a plurality of calculations, determines an operating mode of the engine in response to an engine load and an engine speed, selects one of a plurality of inputs in response to the operating mode of the engine to provide an interpolation weighting factor, the plurality of inputs including the first dynamically determined weighting factor and one or more predetermined weighting factors, utilizes the interpolation weighting factor to interpolate between a first set of combustion control data and a second set of combustion control data to determine a set of combustion control values, and controls operation of the engine using the set of combustion control values.

Abstract: Described herein are various embodiments of an apparatus, a system, and a methods for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one embodiment, an apparatus for controlling an SCR system of an internal combustion engine system includes an ammonia storage module and a reductant dosing module. The ammonia storage module determines an ammonia storage surface coverage on an SCR catalyst of the SCR system and an ammonia compensation value based on one of an excess ammonia flow rate entering the SCR catalyst and an excess NOx flow rate entering the SCR catalyst. The reductant dosing module that generates a reductant dosing command based on the ammonia compensation value.

Abstract: An apparatus for controlling engine operations to a low NOx output amount at low selective catalytic reduction (SCR) temperature values and alternatively for controlling engine operations in an EGR cooler bypass regime at low engine load levels is described. The apparatus includes a controller that interprets a present speed and a present load of an engine, that determines an engine operating region in response to the present speed and the present load, and that provides an EGR cooler bypass command that provides EGR cooler bypass flow in response to the engine operating region being a first, low load, region. The controller operates the engine with supplemental NOx management in response to the engine operating region being a second, intermediate load, region. The controller operates the engine without either of the EGR cooler bypass or the supplemental NOx management in response to the engine operating region being a third region.

Abstract: Described herein are various embodiments of an apparatus, a system, and a methods for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one embodiment, an apparatus for controlling an SCR system of an internal combustion engine system includes an ammonia storage module and a reductant dosing module. The ammonia storage module determines an ammonia storage surface coverage on an SCR catalyst of the SCR system and an ammonia compensation value based on one of an excess ammonia flow rate entering the SCR catalyst and an excess NOx flow rate entering the SCR catalyst. The reductant dosing module that generates a reductant dosing command based on the ammonia compensation value.

Abstract: Described herein are various embodiments of an apparatus, a system, and a methods for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one embodiment, an apparatus for controlling an SCR system of an internal combustion engine system includes an ammonia storage module and a reductant dosing module. The ammonia storage module determines an ammonia storage surface coverage on an SCR catalyst of the SCR system and an ammonia compensation value based on one of an excess ammonia flow rate entering the SCR catalyst and an excess NOx flow rate entering the SCR catalyst. The reductant dosing module that generates a reductant dosing command based on the ammonia compensation value.

Abstract: One embodiment is a method including operating an SCR system at a plurality of commanded ammonia to NOx input ratios, providing a plurality of data indicating NOx output from the SCR system for the plurality of commanded ammonia to NOx input ratios, and evaluating the plurality of data to diagnose the SCR system. Additional embodiment are methods, systems, and apparatuses including SCR diagnostics. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.

Abstract: An apparatus for controlling engine operations to a low NOx output amount at low selective catalytic reduction (SCR) temperature values and alternatively for controlling engine operations in an EGR cooler bypass regime at low engine load levels is described. The apparatus includes a controller that interprets a present speed and a present load of an engine, that determines an engine operating region in response to the present speed and the present load, and that provides an EGR cooler bypass command that provides EGR cooler bypass flow in response to the engine operating region being a first, low load, region. The controller operates the engine with supplemental NOx management in response to the engine operating region being a second, intermediate load, region. The controller operates the engine without either of the EGR cooler bypass or the supplemental NOx management in response to the engine operating region being a third region.

Abstract: According to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust gas stream of an engine system having a selective catalytic reduction (SCR) system with an SCR catalyst positioned downstream of a reductant injector includes a NOx reduction target module and a reductant module. The NOx reduction target module is configured to determine a NOx reduction requirement, which includes an amount of NOx in the exhaust gas stream to be reduced on the SCR catalyst. The reductant module is configured to determine the amount of reductant added to the exhaust gas stream to achieve the NOx reduction requirement. The amount of reductant added to the exhaust gas stream is a function of at least one ammonia storage characteristic of the SCR catalyst, at least one reductant-to-ammonia conversion characteristic, and a conversion capability of an AMOX catalyst in exhaust receiving communication with the SCR catalyst.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement. The apparatus also includes an ammonia storage module that is configured to determine an ammonia storage modifier. An ammonia target module of the apparatus is configured to determine an ammonia addition requirement. The ammonia target module is communicable in data receiving communication with the ammonia storage module to receive the ammonia storage modifier, which is added to the ammonia addition requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement that includes an amount of NOx in the exhaust gas stream to be reduced on a selective catalytic reduction (SCR) catalyst. The apparatus also includes an ammonia target module that is configured to determine an ammonia addition requirement that includes an amount of ammonia added to the exhaust gas stream to achieve the NOx reduction requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is operable to determine a NOx reduction requirement that includes an amount of NOx in the exhaust gas stream to be reduced on a selective catalytic reduction (SCR) catalyst. The apparatus also includes an ammonia target module that is operable to determine an ammonia addition requirement that includes an amount of ammonia added to the exhaust gas stream to achieve the NOx reduction requirement. The apparatus also includes a reductant target module that has a hydrolysis module and an inverse hydrolysis module. The hydrolysis module is operable to determine a predicted amount of ammonia and isocyanic acid entering the SCR catalyst.

Abstract: Described herein are various embodiments of an apparatus, a system, and a methods for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one embodiment, an apparatus for controlling an SCR system of an internal combustion engine system includes an ammonia storage module and a reductant dosing module. The ammonia storage module determines an ammonia storage surface coverage on an SCR catalyst of the SCR system and an ammonia compensation value based on one of an excess ammonia flow rate entering the SCR catalyst and an excess NOx flow rate entering the SCR catalyst. The reductant dosing module that generates a reductant dosing command based on the ammonia compensation value.

Abstract: One embodiment is a method including operating an SCR system at a plurality of commanded ammonia to NOx input ratios, providing a plurality of data indicating NOx output from the SCR system for the plurality of commanded ammonia to NOx input ratios, and evaluating the plurality of data to diagnose the SCR system. Additional embodiment are methods, systems, and apparatuses including SCR diagnostics. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.

Abstract: According to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust gas stream of an engine system having a selective catalytic reduction (SCR) system with an SCR catalyst positioned downstream of a reductant injector includes a NOx reduction target module and a reductant module. The NOx reduction target module is configured to determine a NOx reduction requirement, which includes an amount of NOx in the exhaust gas stream to be reduced on the SCR catalyst. The reductant module is configured to determine the amount of reductant added to the exhaust gas stream to achieve the NOx reduction requirement. The amount of reductant added to the exhaust gas stream is a function of at least one ammonia storage characteristic of the SCR catalyst, at least one reductant-to-ammonia conversion characteristic, and a conversion capability of an AMOX catalyst in exhaust receiving communication with the SCR catalyst.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement. The apparatus also includes an ammonia storage module that is configured to determine an ammonia storage modifier. An ammonia target module of the apparatus is configured to determine an ammonia addition requirement. The ammonia target module is communicable in data receiving communication with the ammonia storage module to receive the ammonia storage modifier, which is added to the ammonia addition requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is operable to determine a NOx reduction requirement that includes an amount of NOx in the exhaust gas stream to be reduced on a selective catalytic reduction (SCR) catalyst. The apparatus also includes an ammonia target module that is operable to determine an ammonia addition requirement that includes an amount of ammonia added to the exhaust gas stream to achieve the NOx reduction requirement. The apparatus also includes a reductant target module that has a hydrolysis module and an inverse hydrolysis module. The hydrolysis module is operable to determine a predicted amount of ammonia and isocyanic acid entering the SCR catalyst.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement that includes an amount of NOx in the exhaust gas stream to be reduced on a selective catalytic reduction (SCR) catalyst. The apparatus also includes an ammonia target module that is configured to determine an ammonia addition requirement that includes an amount of ammonia added to the exhaust gas stream to achieve the NOx reduction requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.