Abstract: A system and method for controlling an aftertreatment assembly includes a diesel oxidation catalyst (DOC) device configured to receive an exhaust gas. One or more sensors are configured to obtain respective sensor data relative to the exhaust gas and DOC device. A controller is in communication with the sensors and configured to obtain respective sensor data relative to the exhaust gas. The controller is configured to determine if one or more enabling conditions are met, including reaching a predefined temperature range in the DOC device. A rich event is induced targeting a predetermined range of a lambda value for a predefined maximum time duration. When the rich event has ended, an exotherm index is obtained for an observation window immediately after the rich event. The controller is configured to control operation of the aftertreatment assembly based at least partially on the exotherm index.

Abstract: A system and method for controlling an aftertreatment assembly includes a diesel oxidation catalyst (DOC) device configured to receive an exhaust gas. One or more sensors are configured to obtain respective sensor data relative to the exhaust gas and DOC device. A controller is in communication with the sensors and configured to obtain respective sensor data relative to the exhaust gas. The controller is configured to determine if one or more enabling conditions are met, including reaching a predefined temperature range in the DOC device. A rich event is induced targeting a predetermined range of a lambda value for a predefined maximum time duration. When the rich event has ended, an exotherm index is obtained for an observation window immediately after the rich event. The controller is configured to control operation of the aftertreatment assembly based at least partially on the exotherm index.

Abstract: An aftertreatment (AT) system for an exhaust gas stream of an internal combustion engine may comprise a selective catalytic reduction (SCR) device, a particulate filter (PF) device, a reducing agent injection system configured to inject a reducing agent into the exhaust gas stream at a location upstream of the SCR device. A reducing agent injection rate control system may be embedded in an engine control module and may be configured to calculate and output a reducing agent injection rate signal and to apply the injection rate signal to the injection system to control the amount of reducing agent injected into the exhaust gas stream. Calculation of the reducing agent injection rate signal may involve applying a dynamic weighting factor to predetermined minimum and maximum allowable injection rates to obtain a weighted injection rate based upon operating parameters of the exhaust gas stream and/or the AT system.

Abstract: An exhaust gas flow after-treatment (AT) system includes first AT device and a second AT device in fluid communication with and positioned in the flow of exhaust gas downstream of the first AT device. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device and an injector for introducing a reductant into the exhaust passage. The AT system additionally includes a variable-position mixer arranged within the exhaust passage downstream of the injector. Furthermore, the AT system includes a mechanism configured to regulate the variable-position mixer between and inclusive of a first mixer position configured to increase a swirling motion and turbulence in the exhaust gas flow within the exhaust passage to thereby mix the reductant with the exhaust gas flow, and a second mixer position configured to reduce a backpressure generated by the mixer.

Abstract: A method of adjusting reductant injection for a selective catalyst reduction device with a soot filter (SCRF) includes calculating, through a processor, an amount of soot in the SCRF, determining, through the processor, a shrinking core model of the SCRF based on the amount of soot, calculating, with the processor using the shrinking core model, an amount of reductant to inject into the SCRF, and injecting the amount of reductant into the SCRF.

Abstract: Systems and methods for controlling a valve for directing an exhaust gas stream through an exhaust duct having a first after treatment device and a second after treatment device in an exhaust system. The method includes receiving sensor signals from a sensor coupled to the second after treatment device. The method includes processing the sensor signals to determine a temperature of the second after treatment device, and determining a position for the valve based on whether the temperature exceeds a pre-defined threshold for the temperature of the second after treatment device. The method includes outputting a control signal to move the valve to a first position in which the exhaust gas stream flows through a first portion of the first after treatment device or a second position in which the exhaust gas stream flows through a second portion of the first after treatment device based on the temperature.

Abstract: An exhaust gas flow after-treatment (AT) system includes first and second AT devices. The first AT device includes cone with an inlet defined by a surface area having a first geometric center and an outlet defined by a surface area having a second geometric center. The AT system also includes an exhaust passage for carrying the exhaust gas flow from the first AT device cone outlet to the second AT device, and includes an injector for introducing a reductant into the exhaust gas flow within the exhaust passage. The first geometric center is arranged at a predetermined distance from the second geometric center and the inlet surface area is greater than the outlet surface area by a predetermined ratio. The predetermined distance and the predetermined ratio are together configured to induce swirl in and mix the reductant with the exhaust gas flow within the exhaust passage.

Abstract: An exhaust gas flow after-treatment (AT) system includes first AT device and a second AT device in fluid communication with and positioned in the flow of exhaust gas downstream of the first AT device. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device and an injector for introducing a reductant into the exhaust passage. The AT system additionally includes a variable-position mixer arranged within the exhaust passage downstream of the injector. Furthermore, the AT system includes a mechanism configured to regulate the variable-position mixer between and inclusive of a first mixer position configured to increase a swirling motion and turbulence in the exhaust gas flow within the exhaust passage to thereby mix the reductant with the exhaust gas flow, and a second mixer position configured to reduce a backpressure generated by the mixer.

Abstract: An exhaust gas flow after-treatment (AT) system includes first and second AT devices. The first AT device includes cone with an inlet defined by a surface area having a first geometric center and an outlet defined by a surface area having a second geometric center. The AT system also includes an exhaust passage for carrying the exhaust gas flow from the first AT device cone outlet to the second AT device, and includes an injector for introducing a reductant into the exhaust gas flow within the exhaust passage. The first geometric center is arranged at a predetermined distance from the second geometric center and the inlet surface area is greater than the outlet surface area by a predetermined ratio. The predetermined distance and the predetermined ratio are together configured to induce swirl in and mix the reductant with the exhaust gas flow within the exhaust passage.

Abstract: A method of adjusting reductant injection for a selective catalyst reduction device with a soot filter (SCRF) includes calculating, through a processor, an amount of soot in the SCRF, determining, through the processor, a shrinking core model of the SCRF based on the amount of soot, calculating, with the processor using the shrinking core model, an amount of reductant to inject into the SCRF, and injecting the amount of reductant into the SCRF.

Abstract: Systems and methods for controlling a valve for directing an exhaust gas stream through an exhaust duct having a first after treatment device and a second after treatment device in an exhaust system. The method includes receiving sensor signals from a sensor coupled to the second after treatment device. The method includes processing the sensor signals to determine a temperature of the second after treatment device, and determining a position for the valve based on whether the temperature exceeds a pre-defined threshold for the temperature of the second after treatment device. The method includes outputting a control signal to move the valve to a first position in which the exhaust gas stream flows through a first portion of the first after treatment device or a second position in which the exhaust gas stream flows through a second portion of the first after treatment device based on the temperature.

Abstract: An after-treatment (AT) system for an exhaust gas flow from an internal combustion engine includes first and second AT devices positioned in the exhaust gas flow. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device. The AT system additionally includes an injector configured to generate a reductant spray into the exhaust passage and a sensor positioned proximate the injector for detecting a concentration of a pollutant in the exhaust gas flow downstream of the first AT device. The AT system furthermore includes a deflector arranged between the injector and the sensor and configured to guide the flow of exhaust gas to the sensor to thereby concentrate the flow of exhaust gas at the sensor and direct the reductant spray away from the sensor to thereby minimize detection of the reductant by the sensor.

Abstract: An after-treatment (AT) system for an exhaust gas flow from an internal combustion engine includes first and second AT devices positioned in the exhaust gas flow. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device. The AT system additionally includes an injector configured to generate a reductant spray into the exhaust passage and a sensor positioned proximate the injector for detecting a concentration of a pollutant in the exhaust gas flow downstream of the first AT device. The AT system furthermore includes a deflector arranged between the injector and the sensor and configured to guide the flow of exhaust gas to the sensor to thereby concentrate the flow of exhaust gas at the sensor and direct the reductant spray away from the sensor to thereby minimize detection of the reductant by the sensor.

Abstract: A mixer includes a plurality of blades extending along a longitudinal axis. The blades are arranged in a single row, and are axially spaced from each other along a transverse axis. Each of the blades defines a window. Each of the blades includes an upstream portion, and a downstream portion. Each of the blades includes a bend at the window that forms an interior blade angle between its respective upstream portion and its respective downstream portion. The single row of the blades is arranged to include a first group of blades and a second group of blades. The interior blade angle of each of the blades in the first group faces in a first axial direction along the transverse axis. The interior blade angle of each of the blades in the second group faces in a second axial direction along the transverse axis.

Abstract: A mixer includes a plurality of blades extending along a longitudinal axis. The blades are arranged in a single row, and are axially spaced from each other along a transverse axis. Each of the blades defines a window. Each of the blades includes an upstream portion, and a downstream portion. Each of the blades includes a bend at the window that forms an interior blade angle between its respective upstream portion and its respective downstream portion. The single row of the blades is arranged to include a first group of blades and a second group of blades. The interior blade angle of each of the blades in the first group faces in a first axial direction along the transverse axis. The interior blade angle of each of the blades in the second group faces in a second axial direction along the transverse axis.

Abstract: A compression-ignition engine is coupled to an exhaust aftertreatment system including a particulate filter. A method of operating the compression-ignition engine includes executing a feed-forward control scheme to determine an amount of post-combustion fuel to achieve a preferred temperature in the exhaust gas feedstream at an inlet to the particulate filter. The amount of post-combustion fuel is a nominal post-combustion fuel amount adjusted for a biodiesel blend ratio of the fuel. The post-combustion fuel is injected upstream of the exhaust aftertreatment system in response to a command to regenerate the particulate filter.

Abstract: A method for detecting the blending level of biodiesel fuel in an internal combustion engine includes setting at least two post injection fuel quantity reference values respectively for known biodiesel blending percentage levels. A post injection fuel quantity value is evaluated and is compared with the at least two post injection fuel quantity reference value. A predetermined correlation set of values between the post injection fuel quantity value and a biodiesel blending level expressed by biodiesel percentage with respect to the petro-diesel is used to determine the biodiesel blending level.

Abstract: A compression-ignition engine is coupled to an exhaust aftertreatment system including a particulate filter. A method of operating the compression-ignition engine includes executing a feed-forward control scheme to determine an amount of post-combustion fuel to achieve a preferred temperature in the exhaust gas feedstream at an inlet to the particulate filter. The amount of post-combustion fuel is a nominal post-combustion fuel amount adjusted for a biodiesel blend ratio of the fuel. The post-combustion fuel is injected upstream of the exhaust aftertreatment system in response to a command to regenerate the particulate filter.

Abstract: A method for operating a compression-ignition engine includes controlling an engine fueling, a compressor boost pressure, and an EGR content in a cylinder charge to maintain engine operation in response to a biodiesel blend ratio of a biodiesel fuel blend.

Abstract: A method for detecting the blending level of biodiesel fuel in an internal combustion engine includes setting at least two post injection fuel quantity reference values respectively for known biodiesel blending percentage levels. A post injection fuel quantity value is evaluated and is compared with the at least two post injection fuel quantity reference value. A predetermined correlation set of values between the post injection fuel quantity value and a biodiesel blending level expressed by biodiesel percentage with respect to the petro-diesel is used to determine the biodiesel blending level.