Abstract: A method includes acquiring nitrogen oxide (NOx) data indicative of a first amount of NOx in an exhaust flow exiting an engine and a second amount of NOx in the exhaust flow exiting an exhaust aftertreatment system coupled to the engine where the exhaust aftertreatment system including a selective catalytic reduction (SCR) system including a SCR catalyst; determining a NOx conversion efficiency fault is present within the exhaust aftertreatment system based on the first amount of NOx and the second amount of NOx; monitoring an actual amount of NOx in the exhaust flow downstream of the SCR catalyst; determining an expected amount of NOx downstream of the SCR catalyst; and determining the SCR catalyst is responsible for the NOx conversion efficiency fault in response to the actual amount of NOx differing from the expected amount of NOx by more than a threshold amount.

Abstract: An apparatus includes an engine module, an in-cylinder content module, and an engine out NOx module. The engine module is structured to interpret engine in-cylinder data regarding an operating condition within a cylinder of an engine, wherein the engine in-cylinder data includes an engine torque, an engine speed, a rail pressure, and a start-of-injection. The in-cylinder content module is structured to interpret at least one additional in-cylinder data point regarding the operating condition within the cylinder of the engine. The engine out NOx module is structured to determine an engine out NOx amount responsive to the engine in-cylinder data and the at least one additional in-cylinder data point.

Abstract: A method includes acquiring nitrogen oxide (NOx) data indicative of a first amount of NOx in an exhaust flow exiting an engine and a second amount of NOx in the exhaust flow exiting an exhaust aftertreatment system coupled to the engine where the exhaust aftertreatment system including a selective catalytic reduction (SCR) system including a SCR catalyst; determining a NOx conversion efficiency fault is present within the exhaust aftertreatment system based on the first amount of NOx and the second amount of NOx; monitoring an actual amount of NOx in the exhaust flow downstream of the SCR catalyst; determining an expected amount of NOx downstream of the SCR catalyst; and determining the SCR catalyst is responsible for the NOx conversion efficiency fault in response to the actual amount of NOx differing from the expected amount of NOx by more than a threshold amount.

Abstract: A method includes interpreting NOx data indicative of an amount of NOx exiting an engine and an amount of NOx exiting an exhaust aftertreatment system coupled to the engine, determining a NOx conversion efficiency fault is present based on the amount of NOx exiting the engine and the amount of NOx exiting the exhaust aftertreatment system, and determining at least one of a selective catalytic reduction (SCR) catalyst of the exhaust aftertreatment system and a diesel particulate filter having a coating of a SCR reaction catalyst (DPF-SCR) of the exhaust aftertreatment system are responsible for the NOx conversion efficiency fault based on at least one of a reductant slip amount and a NOx conversion value across at least one of the SCR catalyst and the DPF-SCR.

Abstract: Systems, apparatus and methods are provided for reducing reductant consumption in an exhaust aftertreatment system that includes a first SCR device and a downstream second SCR device, a first reductant injector upstream of the first SCR device, and a second reductant injector between the first and second SCR devices. NOx conversion occurs with reductant injection by the first reductant injector to the first SCR device in a first temperature range and with reductant injection by the second reductant injector to the second SCR device when the temperature of the first SCR device is above a reductant oxidation conversion threshold.

Abstract: A method includes interpreting NOx data indicative of an amount of NOx exiting an engine and an amount of NOx exiting an exhaust aftertreatment system coupled to the engine, determining a NOx conversion efficiency fault is present based on the amount of NOx exiting the engine and the amount of NOx exiting the exhaust aftertreatment system, and determining at least one of a selective catalytic reduction (SCR) catalyst of the exhaust aftertreatment system and a diesel particulate filter having a coating of a SCR reaction catalyst (DPF-SCR) of the exhaust aftertreatment system are responsible for the NOx conversion efficiency fault based on at least one of a reductant slip amount and a NOx conversion value across at least one of the SCR catalyst and the DPF-SCR.

Abstract: An apparatus includes an engine module, an in-cylinder content module, and an engine out NOx module. The engine module is structured to interpret engine in-cylinder data regarding an operating condition within a cylinder of an engine, wherein the engine in-cylinder data includes an engine torque, an engine speed, a rail pressure, and a start-of-injection. The in-cylinder content module is structured to interpret at least one additional in-cylinder data point regarding the operating condition within the cylinder of the engine. The engine out NOx module is structured to determine an engine out NOx amount responsive to the engine in-cylinder data and the at least one additional in-cylinder data point.

Abstract: An apparatus includes a nitrogen oxide (NOx) module and a selective catalytic reduction (SCR) diagnostic module. The NOx module is in exhaust gas communication with an exhaust flow of an exhaust aftertreatment system from an engine. The NOx module is structured to interpret NOx data indicative of an amount of NOx exiting the engine and an amount of NOx exiting the exhaust aftertreatment system, and determine a NOx conversion efficiency fault is present based on the amount of NOx exiting the engine and the amount of NOx exiting the exhaust aftertreatment system. The SCR diagnostic module is structured to determine at least one of a SCR catalyst and a diesel particulate filter including a coating of a SCR reaction catalyst (DPF-SCR) are responsible for the NOx conversion efficiency fault based on at least one of a reductant slip amount and a NOx conversion value across at least one of the SCR catalyst and the DPF-SCR.

Abstract: Disclosed are methods, systems, and computer-readable mediums for determining combustion properties of wellhead gas. A methane concentration of a gas mixture is measured. A non-methane hydrocarbon concentration of the gas mixture is measured. An inert concentration of the gas mixture is calculated. A first surrogate for the non-methane hydrocarbon concentration is selected, where the first surrogate is selected as propane if the methane concentration is greater than a first threshold, and where the first surrogate is selected as pentane if the methane concentration is less than or equal to the first threshold. A methane number of the gas mixture is determined, where the methane number is based on the methane concentration, the first surrogate, and the inert concentration.

Abstract: Systems and methods are provided for managing low temperature NOx and HC emissions, such as during a cold start of an internal combustion engine. The systems and methods include storing NOx and HC emissions at low temperatures and passively releasing and treating these emissions as the temperature of the exhaust system increases.

Abstract: Systems, apparatus and methods are provided for reducing reductant consumption in an exhaust aftertreatment system that includes a first SCR device and a downstream second SCR device, a first reductant injector upstream of the first SCR device, and a second reductant injector between the first and second SCR devices. NOx conversion occurs with reductant injection by the first reductant injector to the first SCR device in a first temperature range and with reductant injection by the second reductant injector to the second SCR device when the temperature of the first SCR device is above a reductant oxidation conversion threshold.

Abstract: An apparatus includes a nitrogen oxide (NOx) module and a selective catalytic reduction (SCR) diagnostic module. The NOx module is in exhaust gas communication with an exhaust flow of an exhaust aftertreatment system from an engine. The NOx module is structured to interpret NOx data indicative of an amount of NOx exiting the engine and an amount of NOx exiting the exhaust aftertreatment system, and determine a NOx conversion efficiency fault is present based on the amount of NOx exiting the engine and the amount of NOx exiting the exhaust aftertreatment system. The SCR diagnostic module is structured to determine at least one of a SCR catalyst and a diesel particulate filter including a coating of a SCR reaction catalyst (DPF-SCR) are responsible for the NOx conversion efficiency fault based on at least one of a reductant slip amount and a NOx conversion value across at least one of the SCR catalyst and the DPF-SCR.

Abstract: Systems, apparatus and methods are provided for reducing reductant consumption in an exhaust aftertreatment system that includes a first SCR device and a downstream second SCR device, a first reductant injector upstream of the first SCR device, and a second reductant injector between the first and second SCR devices. NOx conversion occurs with reductant injection by the first reductant injector to the first SCR device in a first temperature range and with reductant injection by the second reductant injector to the second SCR device when the temperature of the first SCR device is above a reductant oxidation conversion threshold.

Abstract: Disclosed are methods, systems, and computer-readable mediums for predicting a driving intention of a driver of a vehicle. A sequence comprising a plurality of indicators is detected, where each indicator suggests intent to drive a vehicle. A separation time between each of the indicators of the sequence is determined. The sequence and determined separation times are compared to historical data, where the historical data comprises data related to previously stored separation times of the sequence. Based on the comparison, a confidence level that an engine of the vehicle will be started is determined. Based on the confidence level, a feature of the vehicle is activated.

Abstract: Disclosed are methods, systems, and computer-readable mediums for predicting a driving intention of a driver of a vehicle. A sequence comprising a plurality of indicators is detected, where each indicator suggests intent to drive a vehicle. A separation time between each of the indicators of the sequence is determined. The sequence and determined separation times are compared to historical data, where the historical data comprises data related to previously stored separation times of the sequence. Based on the comparison, a confidence level that an engine of the vehicle will be started is determined. Based on the confidence level, a feature of the vehicle is activated.

Abstract: Systems, apparatus and methods are provided for reducing reductant consumption in an exhaust aftertreatment system that includes a first SCR device and a downstream second SCR device, a first reductant injector upstream of the first SCR device, and a second reductant injector between the first and second SCR devices. NOx conversion occurs with reductant injection by the first reductant injector to the first SCR device in a first temperature range and with reductant injection by the second reductant injector to the second SCR device when the temperature of the first SCR device is above a reductant oxidation conversion threshold.

Abstract: Disclosed are methods, systems, and computer-readable mediums for determining combustion properties of wellhead gas. A methane concentration of a gas mixture is measured. A non-methane hydrocarbon concentration of the gas mixture is measured. An inert concentration of the gas mixture is calculated. A first surrogate for the non-methane hydrocarbon concentration is selected, where the first surrogate is selected as propane if the methane concentration is greater than a first threshold, and where the first surrogate is selected as pentane if the methane concentration is less than or equal to the first threshold. A methane number of the gas mixture is determined, where the methane number is based on the methane concentration, the first surrogate, and the inert concentration.

Abstract: Systems and methods are provided for managing low temperature NOx and HC emissions, such as during a cold start of an internal combustion engine. The systems and methods include storing NOx and HC emissions at low temperatures and passively releasing and treating these emissions as the temperature of the exhaust system increases.