Abstract: Systems and associated methods of treating diesel exhaust in a vehicle are disclosed. An example method includes providing an exhaust aftertreatment device in an exhaust tailpipe, and a first nitrogen oxide (NOx) sensor upstream of the exhaust aftertreatment device, with the exhaust aftertreatment device configured to reduce NOx present in an exhaust flow through the exhaust aftertreatment device with a treatment fluid applied to the exhaust flow. This example method may also include measuring a concentration of NOx in the exhaust flow with the first sensor, determining an error in the measurement of the NOx concentration, and applying a learning corrective adjustment in a subsequent measurement of the NOx concentration in the exhaust flow in response to that determination. A first magnitude of the learning corrective adjustment may be based at least in part upon a second magnitude of the error in the measurement.

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: A method for treating exhaust gas from an internal combustion engine including, determining if a steady state condition exist and perturbing a reductant injection corresponding the steady state. Measuring a first and a second NOx values corresponding to the steady state and resulting from the perturbation, and computing a gradient of the NOx values relative to the steady state respectively. The method also includes comparing the gradient of the second NOx value with one of the first NOx value, if the gradient of the first NOx value is within a selected range of the gradient of the second NOx value, identifying poor efficiency operation for the engine and setting an estimated reductant storage at zero. Otherwise if the gradient of the second NOx value exceeds a selected threshold, identifying a reductant slip condition and setting the estimated storage at maximum, if not, making no corrections in estimated storage.

Abstract: Described herein is a method for detecting steady state ammonia slip for a motor vehicle having an internal combustion engine and an emissions control system. The emissions control system includes a selective catalytic reduction (SCR) device, a NOx sensor, and a controller. The controller executes a method for ammonia slip detection that includes determining if the SCR device is at steady state, comparing a NOx measurement from the NOx sensor with a predicted NOx value. If the NOx measurement exceeds the predicted NOx value by a threshold, perturbing a reductant injection, the perturbation having a selected magnitude and a selected duration. The method also includes measuring a NOx value resulting from the perturbation and computing a gradient thereof relative to the measured NOx, and ascertaining if a gradient of the NOx resulting from the perturbation exceeds a threshold and identifying a reductant slip condition if so.

Abstract: A method and system is disclosed to test for a proper functioning of a selective catalytic reduction system of an internal combustion engine. The engine is operated at idle speed and a functionality check of the pressure sensor is executed. The engine is operated to increase an exhaust gas temperature in the exhaust pipe upstream of the catalyst and a functionality check of the pump is executed. A functionality check of the injector is executed after the functionality check of the pump and once the exhaust gas temperature has reached a predetermined target value thereof. A functionality check of the supply conduit is executed after the functionality check of the injector. The selective catalytic reduction system is identified as functioning properly when all of the functionality checks yields a positive result or malfunctioning when any one of the functionality checks yields a negative result.

Abstract: A method for treating exhaust gas from an internal combustion engine including, determining if a steady state condition exist and perturbing a reductant injection corresponding the steady state. Measuring a first and a second NOx values corresponding to the steady state and resulting from the perturbation, and computing a gradient of the NOx values relative to the steady state respectively. The method also includes comparing the gradient of the second NOx value with one of the first NOx value, if the gradient of the first NOx value is within a selected range of the gradient of the second NOx value, identifying poor efficiency operation for the engine and setting an estimated reductant storage at zero. Otherwise if the gradient of the second NOx value exceeds a selected threshold, identifying a reductant slip condition and setting the estimated storage at maximum, if not, making no corrections in estimated storage.

Abstract: Described herein is a method for detecting steady state ammonia slip for a motor vehicle having an internal combustion engine and an emissions control system. The emissions control system includes a selective catalytic reduction (SCR) device, a NOx sensor, and a controller. The controller executes a method for ammonia slip detection that includes determining if the SCR device is at steady state, comparing a NOx measurement from the NOx sensor with a predicted NOx value. If the NOx measurement exceeds the predicted NOx value by a threshold, perturbing a reductant injection, the perturbation having a selected magnitude and a selected duration. The method also includes measuring a NOx value resulting from the perturbation and computing a gradient thereof relative to the measured NOx, and ascertaining if a gradient of the NOx resulting from the perturbation exceeds a threshold and identifying a reductant slip condition if so.

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: A computer program, system and method are provided for thermally regulating an injector injecting a reducing agent into an exhaust pipe of an internal combustion engine. A pump is activated to deliver a coolant in a coolant circuit having a portion in heat exchange relation with the injector. A value is determined for a mass flow rate of the coolant delivered by the pump. A value is calculated for a temperature of the injector as a function of the determined value of the mass flow rate. A difference is calculated between the calculated value of the injector temperature and a predetermined set-point value thereof, and the mass flow rate of the coolant delivered by the pump is adjusted on the basis of the calculated difference.

Abstract: A method of monitoring the reductant delivery performance of a selective catalytic reduction component of a vehicle exhaust system, includes operating a diesel exhaust fluid pump until a reductant delivery performance pressure setpoint is reached. Calculating an average pump duty cycle and commanding the calculated pump duty cycle to be used in the open loop control phase. Calculating an initial average pressure. Injecting a controlled diesel exhaust fluid (DEF). Calculating a final average pressure. Calculating a pressure drop ?P and determining if the calculated pressure drop ?P is less than an expected pressure drop calculated as a function of the average pump duty cycle.

Abstract: A method of monitoring the reductant delivery performance of a selective catalytic reduction component of a vehicle exhaust system, includes operating a diesel exhaust fluid pump until a reductant delivery performance pressure setpoint is reached. Calculating an average pump duty cycle and commanding the calculated pump duty cycle to be used in the open loop control phase. Calculating an initial average pressure. Injecting a controlled diesel exhaust fluid (DEF). Calculating a final average pressure. Calculating a pressure drop ?P and determining if the calculated pressure drop ?P is less than an expected pressure drop calculated as a function of the average pump duty cycle.

Abstract: A method and system is disclosed to test for a proper functioning of a selective catalytic reduction system of an internal combustion engine. The engine is operated at idle speed and a functionality check of the pressure sensor is executed. The engine is operated to increase an exhaust gas temperature in the exhaust pipe upstream of the catalyst and a functionality check of the pump is executed. A functionality check of the injector is executed after the functionality check of the pump and once the exhaust gas temperature has reached a predetermined target value thereof. A functionality check of the supply conduit is executed after the functionality check of the injector. The selective catalytic reduction system is identified as functioning properly when all of the functionality checks yields a positive result or malfunctioning when any one of the functionality checks yields a negative result.

Abstract: A computer program, system and method are provided for thermally regulating an injector injecting a reducing agent into an exhaust pipe of an internal combustion engine. A pump is activated to deliver a coolant in a coolant circuit having a portion in heat exchange relation with the injector. A value is determined for a mass flow rate of the coolant delivered by the pump. A value is calculated for a temperature of the injector as a function of the determined value of the mass flow rate. A difference is calculated between the calculated value of the injector temperature and a predetermined set-point value thereof, and the mass flow rate of the coolant delivered by the pump is adjusted on the basis of the calculated difference.