Abstract: An engine control system includes an engine calibration module that sets fuel injection timing based on one of N cetane number (CN) values, wherein N is an integer greater than one. A combustion noise module generates a combustion noise signal based on cylinder pressure in a compression ignition (CI) engine during combustion. A fuel quality determination module compares the combustion noise signal to N predetermined combustion noise levels corresponding to the N CN values, and that selects the one of the N CN values based on the comparison.

Abstract: An exhaust treatment system for an internal combustion engine having improved mixing of an injected fluid comprises an exhaust gas conduit configured to receive exhaust gas from an internal combustion engine and to deliver the exhaust gas to the exhaust treatment system. A fluid injector in fluid communication with the exhaust gas conduit configured delivers a fluid into the exhaust gas and an evaporation volume disposed in the exhaust conduit downstream of the fluid injector is configured to slow the bulk velocity of the fluid and exhaust gas mixture to thereby increase the residence time of the exhaust gas mixture therein. An exhaust treatment device is configured to receive the fluid and exhaust gas mixture.

Abstract: A control system includes an upstream nitrogen oxide (NOx) control module that increases an upstream NOx level based on an initial upstream NOx level in an exhaust system, and an ammonia (NH3) storage condition detection module that detects a NH3 storage condition based on a difference in a downstream NOx level before and after the upstream NOx level is increased. A method includes increasing an upstream NOx level based on an initial upstream NOx level in an exhaust system, and detecting an NH3 storage condition based on a difference in a downstream NOx level before and after the upstream NOx level is increased.

Abstract: An exhaust treatment system for an internal combustion engine having improved mixing of an injected fluid comprises an exhaust gas conduit configured to receive exhaust gas from an internal combustion engine and to deliver the exhaust gas to the exhaust treatment system. A fluid injector in fluid communication with the exhaust gas conduit configured delivers a fluid into the exhaust gas and an evaporation volume disposed in the exhaust conduit downstream of the fluid injector is configured to slow the bulk velocity of the fluid and exhaust gas mixture to thereby increase the residence time of the exhaust gas mixture therein. An exhaust treatment device is configured to receive the fluid and exhaust gas mixture.

Abstract: An internal combustion engine has an exhaust treatment system with a fluid injection system and a swirl can plenum mixer for mixing injected fluid with exhaust gas exhausted from the engine. The mixer comprises a canister having an inner plenum. A bulkhead separates the inner plenum into an exhaust gas collector and a diffuser chamber. A flow port opens through the bulkhead to a tangential flow director on the downstream side of the bulkhead to collect the exhaust gas. A fluid injector port receives a fluid injector for dispensing a fluid into the exhaust gas for mixing with the exhaust gas in the swirl can plenum mixer. A tangential flow director nozzle is configured to dispense the exhaust gas and fluid into the downstream plenum in a tangential flow trajectory, wherein mixing and vaporization of the exhaust gas and fluid mixture with the exhaust gas is accomplished.

Abstract: An engine air system for charge flow temperature estimation includes a charge air cooler outlet temperature sensor configured to provide a first temperature signal, an exhaust gas recirculation outlet temperature sensor configured to provide a second temperature signal, and a control module configured to receive the first temperature signal and the second temperature signal. The control module includes a charge flow temperature estimation module configured to determine an the estimated charge flow temperature at an intake manifold temperature sensing position based on a combination of the first temperature signal multiplied by an estimated fresh air fraction and the second temperature signal multiplied by an exhaust gas recirculation fraction.

Abstract: An internal combustion engine includes a particulate filter that is configured to treat exhaust gas. A method for monitoring the particulate filter includes employing a soot sensor to monitor the exhaust gas downstream of the particulate filter. A fault is detected in the particulate filter when accumulated soot mass indicated by the soot sensor exceeds a soot mass threshold over a course of engine operation between a first regeneration event and a second regeneration event of the particulate filter. A control module associated with operation of the internal combustion engine is notified of the fault.

Abstract: A method for assessing NO2 generation efficiency in a diesel engine after-treatment (AT) system having a diesel oxidation catalyst (DOC) downstream of the engine generating the NO2 and a selective catalytic reduction (SCR) catalyst downstream of the DOC converting NOX with the aid of the NO2. Engine exhaust gas flow is passed into the AT system and a reductant is injected into the gas flow between the DOC and the SCR catalyst. SCR inlet gas flow temperature is monitored during transient engine operation and DOC inlet and SCR catalyst outlet NOX concentrations are detected when the SCR catalyst inlet gas flow temperature is in a predetermined range. SCR catalyst NOX conversion efficiency is determined using the detected DOC inlet and SCR catalyst outlet concentrations of NOX. Additionally, whether the NO2 generation efficiency is at or above threshold efficiency is assessed by comparing the determined and threshold NOX conversion efficiencies.

Abstract: A mixing plenum for exhaust gas comprises a canister with an inlet and an outlet. A bulkhead is located downstream from the inlet to define an exhaust gas consolidation chamber. An opening in the bulkhead allows exhaust gas to enter a u-shape conduit configured to direct the exhaust gas from a downstream direction to an upstream direction before releasing the exhaust gas back into the plenum downstream of the bulkhead. An injector is configured to inject fluid into the exhaust gas entering the conduit. A conduit exit located a distance “E” from the downstream side of the bulkhead allows the exhaust gas/fluid mixture to exit the conduit into a larger exit volume of the compact mixing can, in the manner of an expansion chamber, where its velocity slows and further mixing of the fluid/exhaust gas occurs and exits the compact mixing can through the outlet flange.

Abstract: An internal combustion engine has an exhaust treatment system with a fluid injection system and a swirl can plenum mixer for mixing injected fluid with exhaust gas exhausted from the engine. The mixer comprises a canister having an inner plenum. A bulkhead separates the inner plenum into an exhaust gas collector and a diffuser chamber. A flow port opens through the bulkhead to a tangential flow director on the downstream side of the bulkhead to collect the exhaust gas. A fluid injector port receives a fluid injector for dispensing a fluid into the exhaust gas for mixing with the exhaust gas in the swirl can plenum mixer. A tangential flow director nozzle is configured to dispense the exhaust gas and fluid into the downstream plenum in a tangential flow trajectory, wherein mixing and vaporization of the exhaust gas and fluid mixture with the exhaust gas is accomplished.

Abstract: A method of assessing non-methane hydrocarbon (NMHC) conversion efficiency in a diesel after-treatment (AT) system having a diesel oxidation catalyst (DOC) arranged upstream of a diesel particulate filter (DPF) includes regenerating the AT system. Additionally, the method monitors DOC inlet and outlet temperatures during the regeneration. The method also assesses whether the DOC is operating at or above threshold efficiency by determining a DOC inlet/outlet temperature difference and comparing the determined inlet/outlet temperature difference with a threshold inlet/outlet temperature difference. The method also monitors DPF outlet temperature if the DOC is operating at or above the threshold efficiency and determines a DOC temperature/DPF outlet temperature difference.

Abstract: A control method for monitoring a soot sensor of an exhaust treatment system is provided. The control method includes: determining when regeneration has completed; comparing soot sensor data to an estimated soot data based on the determining; and generating a message based on the comparing.

Abstract: An exhaust treatment system for an internal combustion engine comprises an exhaust gas conduit configured to receive an exhaust gas from the internal combustion engine and to deliver the exhaust gas to an exhaust treatment device. A fluid delivery system is located upstream of the exhaust treatment device and is configured to deliver a fluid thereto. It comprises a fluid injector, a fluid tube in fluid communication with the fluid injector and extending radially into the exhaust gas conduit for receipt of fluid from a spray tip of the fluid injector, a controller configured to energize the fluid injector to deliver fluid to the fluid tube, and opening(s) in the tube, disposed beyond the boundary layer of exhaust gas flow in the exhaust gas conduit, for release of the fluid into the exhaust gas flow.

Abstract: An engine air system for charge flow temperature estimation includes a charge air cooler outlet temperature sensor configured to provide a first temperature signal, an exhaust gas recirculation outlet temperature sensor configured to provide a second temperature signal, and a control module configured to receive the first temperature signal and the second temperature signal. The control module includes a charge flow temperature estimation module configured to determine an the estimated charge flow temperature at an intake manifold temperature sensing position based on a combination of the first temperature signal multiplied by an estimated fresh air fraction and the second temperature signal multiplied by an exhaust gas recirculation fraction.

Abstract: An internal combustion engine includes a particulate filter that is configured to treat exhaust gas. A method for monitoring the particulate filter includes employing a soot sensor to monitor the exhaust gas downstream of the particulate filter. A fault is detected in the particulate filter when accumulated soot mass indicated by the soot sensor exceeds a soot mass threshold over a course of engine operation between a first regeneration event and a second regeneration event of the particulate filter. A control module associated with operation of the internal combustion engine is notified of the fault.

Abstract: Methods and systems for detecting faults with nitrogen oxides sensors used to detect the presence of nitrogen oxides in an exhaust effluent gas stream emitted from a combustion engine during its operation include providing a virtual nitrogen oxides sensor measurement compared with actual nitrogen oxides content measured by nitrogen oxides sensors.

Abstract: A method for assessing NO2 generation efficiency in a diesel engine after-treatment (AT) system having a diesel oxidation catalyst (DOC) downstream of the engine generating the NO2 and a selective catalytic reduction (SCR) catalyst downstream of the DOC converting NOX with the aid of the NO2. Engine exhaust gas flow is passed into the AT system and a reductant is injected into the gas flow between the DOC and the SCR catalyst. SCR inlet gas flow temperature is monitored during transient engine operation and DOC inlet and SCR catalyst outlet NOX concentrations are detected when the SCR catalyst inlet gas flow temperature is in a predetermined range. SCR catalyst NOX conversion efficiency is determined using the detected DOC inlet and SCR catalyst outlet concentrations of NOX. Additionally, whether the NO2 generation efficiency is at or above threshold efficiency is assessed by comparing the determined and threshold NOX conversion efficiencies.

Abstract: A method of assessing non-methane hydrocarbon (NMHC) conversion efficiency in a diesel after-treatment (AT) system having a diesel oxidation catalyst (DOC) arranged upstream of a diesel particulate filter (DPF) includes regenerating the AT system. Additionally, the method monitors DOC inlet and outlet temperatures during the regeneration. The method also assesses whether the DOC is operating at or above threshold efficiency by determining a DOC inlet/outlet temperature difference and comparing the determined inlet/outlet temperature difference with a threshold inlet/outlet temperature difference. The method also monitors DPF outlet temperature if the DOC is operating at or above the threshold efficiency and determines a DOC temperature/DPF outlet temperature difference.

Abstract: A mixing plenum for exhaust gas comprises a canister with an inlet and an outlet. A bulkhead is located downstream from the inlet to define an exhaust gas consolidation chamber. An opening in the bulkhead allows exhaust gas to enter a u-shape conduit configured to direct the exhaust gas from a downstream direction to an upstream direction before releasing the exhaust gas back into the plenum downstream of the bulkhead. An injector is configured to inject fluid into the exhaust gas entering the conduit. A conduit exit located a distance “E” from the downstream side of the bulkhead allows the exhaust gas/fluid mixture to exit the conduit into a larger exit volume of the compact mixing can, in the manner of an expansion chamber, where its velocity slows and further mixing of the fluid/exhaust gas occurs and exits the compact mixing can through the outlet flange.

Abstract: An exhaust gas aftertreatment system for a diesel engine is provided. The system includes a controller operably coupled to the engine that induces the engine to combust a rich air/fuel mixture in at least one cylinder at a predetermined time interval after startup of the engine to output exhaust gases including elevated levels of CO, and a percentage increase in HC that is less than a minimal threshold percentage relative to combusting a lean air/fuel mixture. The system further includes a diesel oxidation catalyst that receives the exhaust gases and oxidizes the CO to obtain an exothermic reaction that increases a temperature of the exhaust gases flowing through the oxidation catalyst to greater than a threshold temperature level. The system further includes an SCR catalyst which receives the exhaust gases and reduces NOx in the exhaust gases.