Abstract: System and methods for detecting NH3 slip using cross-sensitivity of an NOx sensor may include accessing a temperature value for a catalyst and determining the temperature value for the catalyst exceeds a predetermined value. If the temperature exceeds the predetermined value, a system-out NOx measurement signal from the system-out NOx sensor and an estimated system-out NOx value are used to calculate a delta value. A flag is set indicative of NH3 slip for an exhaust system responsive to an average of delta values for a predetermined period of time exceeding a predetermined value. If the temperature does not exceed the predetermined value, then an average of a plurality of system-out NOx measurement signals can be calculated and a flag is set indicative of NH3 slip responsive to the calculated average for a predetermined period of time exceeding a predetermined value.

Abstract: A sensor mounting table for mounting sensors to an aftertreatment system may include a sensor mounting plate having a substantially flat mounting surface for mounting one or more sensors associated with the aftertreatment system. The substantially flat mounting surface may be offset from a heat shield of the aftertreatment system. The sensor mounting table may further include an insulative material disposed between at least a portion of the substantially flat mounting surface of the sensor mounting plate and the heat shield. The sensor mounting plate may be configured to be attached to the aftertreatment system to secure the insulative material between the substantially flat mounting surface of the sensor mounting plate and the heat shield.

Abstract: An aftertreatment component's shape, entrance geometry, and/or position within an aftertreatment assembly can be modified for local and/or bulk exhaust flow control. In some implementations, a body of the aftertreatment component has a non-circular cross-section, a non-circular opening, and/or a variable face geometry. The non-circular cross-section and/or opening can be of a variety of different shapes.

Abstract: A particulate filter for use in an exhaust aftertreatment system includes a ceramic substrate and an ash layer deposited atop the ceramic substrate. The ash layer has a uniform ash density of at least 0.4 g/L of the ceramic substrate. A method of depositing ash layers in a particulate filter of an exhaust aftertreatment system includes providing a ceramic substrate, preconditioning the ceramic substrate, depositing at least one ash layer atop the ceramic substrate during the preconditioning, monitoring uptake of soot into the particulate filter by measuring an increase in pressure drop across the particulate filter.

Abstract: A selective catalytic reduction system may include a single housing defining a single centerline axis. The selective catalytic reduction system may also include a diesel particulate filter disposed within the single housing and having a DPF center axis aligned with the single centerline axis. The selective catalytic reduction system may also include an SCR catalyst disposed within the single housing and having a center axis aligned with the single centerline axis. In some implementations, the diesel particulate filter may include one or more SiC filters. In some implementations, the SCR catalyst may include one or more extruded SCR catalysts.

Abstract: A system for determining an exhaust flow rate of an exhaust gas produced by an engine comprises a first sensor configured to measure an amount of NOx gases in the exhaust gas. A controller is communicatively coupled to the first sensor. The controller is configured to receive a first sensor signal from the first sensor. The controller is also configured to receive a fuel rate signal corresponding to a rate of fuel consumption by the engine. The controller is configured to determine an air-fuel ratio from the first sensor signal and determine a fuel rate from the fuel rate signal. Furthermore, the controller is configured to determine the exhaust flow rate from the air-fuel ratio and the fuel rate.

Abstract: An aftertreatment system includes: a selective catalytic reduction (SCR) system configured to decompose constituents of exhaust gas; an exhaust conduit configured to deliver the exhaust gas to the SCR system; a hydrocarbon insertion assembly; a valve operably coupled to the exhaust conduit, the valve configured to be selectively opened so as to allow a first gas to enter the exhaust conduit and mix with the exhaust gas; and a controller configured to: determine a SCR system temperature, in response to the SCR system temperature being less than a target temperature, instruct the hydrocarbon insertion assembly to insert hydrocarbons into the exhaust gas, and in response to the SCR system temperature being greater than the target temperature, instruct the valve to open so as to allow the first gas to enter the exhaust conduit, a first gas temperature of the first gas being lower than the SCR system temperature.

Abstract: A dosing lance assembly for an exhaust component includes a housing and a delivery conduit. The housing includes a plate, an endcap, and a pipe. The plate has a first channel. The endcap has a second channel. The pipe has a first end coupled to the plate and a second end coupled to the endcap. The delivery conduit has a first end coupled to the plate and a second end coupled to the endcap, such that reductant is flowable from the first channel to the second channel. When the housing is at an ambient temperature, (i) a length of the delivery conduit is greater than (ii) a first distance between a location at which the first end of the pipe is coupled to the plate and a location at which the second end of the pipe is coupled to the endcap.

Abstract: An exhaust aftertreatment assembly and method of manufacturing and operating an exhaust aftertreatment assembly. An exhaust aftertreatment assembly includes an aftertreatment housing and an inlet conduit coupled to the aftertreatment housing at an inlet port so as to transfer exhaust gas into the aftertreatment housing. An inlet chamber is positioned in the aftertreatment housing. The inlet chamber is fluidly coupled to the inlet port of the aftertreatment housing to receive the exhaust gas from the inlet conduit.

Abstract: A reductant insertion assembly for inserting a reductant into an aftertreatment system includes: a pump assembly comprising a pump that includes a pump outlet; a first metering assembly fluidly coupled to the pump outlet, the first metering assembly comprising a first metering manifold; and a second metering assembly fluidly coupled in series with the pump, the second metering assembly being a separate structure from the first metering assembly and comprising a second metering manifold removably coupled to the first metering manifold. The pump is configured to pump the reductant to the first metering assembly, and to the second metering assembly via the first metering assembly.

Abstract: A process for controlled heating of a sensor of an aftertreatment system comprising accessing several parameters, including an exhaust mass flow, an outlet temperature, an ambient air temperature, and an ambient air velocity, calculating a temperature of the sensor based on a thermal model and the accessed parameters, comparing the calculated temperature to a threshold temperature, and activating a controlled heating process for the sensor responsive to the calculated temperature being below the threshold temperature. The controlled heating process can include activating a heater to heat the sensor.

Abstract: A system may include a NOx sensor and a controller. The controller may be configured to interpret a value of a first parameter indicative of an amount of NOx measured by the NOx sensor and interpret a value of a second parameter for a NOx value from a look-up table. The controller may be further configured to determine a correction factor based on the value of the first parameter and the value of the second parameter and generate a dosing command based, at least in part, on the determined correction factor. In some implementations, the NOx value from the look-up table may be based on one or more operating conditions of an engine. In some implementations, the controller may be further configured to update a NOx value of the look-up table based on the determined correction factor.

Abstract: An exhaust aftertreatment system includes a diesel oxidation catalyst in exhaust gas receiving communication with an engine. A selective catalytic reduction catalyst on filter (SCR on filter) is positioned downstream of the diesel oxidation catalyst. A hydrocarbon doser is configured to inject hydrocarbons into a flow of the exhaust gas upstream of the diesel oxidation catalyst. A reductant doser is configured to inject reductant into the flow of the exhaust gas upstream of the SCR on filter and downstream of the diesel oxidation catalyst. An aftertreatment controller is operatively coupled to the hydrocarbon doser. The aftertreatment controller is configured to control a dosing rate at which the hydrocarbon doser injects hydrocarbons into the flow of the exhaust gas so as to cause regeneration of the SCR on filter.

Abstract: A vane swirl mixer for exhaust aftertreatment includes: a vane swirl mixer inlet; a vane swirl mixer outlet; a first flow device including: a Venturi body; a plurality of upstream vanes positioned within the Venturi body; a plurality of upstream vane apertures interspaced between the plurality of upstream vanes; a plurality of downstream vanes positioned within the Venturi body; and a plurality of downstream vane apertures interspaced between the plurality of downstream vanes. At least one of the upstream vane hub and the downstream vane hub is radially offset from a Venturi center axis, thereby causing individual ones of the plurality of vanes coupled to the radially offset vane hub to differ in their geometry.

Abstract: A selective catalytic reduction system may include a single housing defining a single centerline axis. The selective catalytic reduction system may also include a diesel particulate filter disposed within the single housing and having a DPF center axis aligned with the single centerline axis. The selective catalytic reduction system may also include an SCR catalyst disposed within the single housing and having a center axis aligned with the single centerline axis. In some implementations, the diesel particulate filter may include one or more SiC filters. In some implementations, the SCR catalyst may include one or more extruded SCR catalysts.

Abstract: A collection system for a vehicle that includes a chassis supporting the vehicle above a ground surface, a braking system coupled to the chassis, and a movement member supporting the chassis on the ground surface, includes a first duct, a first collecting conduit, a filter, and a fan. The first duct is configured to be coupled to the chassis proximate at least one of the braking system or the movement member such that the first duct is positioned proximate to the at least one of the braking system or the movement member. The first collecting conduit is fluidly coupled to the first duct. The filter is fluidly coupled to the first collecting conduit. The fan is fluidly coupled to the filter and configured to create a suction force. The fan, the filter, and the first collecting conduit are configured to provide the suction force to the first duct.

Abstract: A system can include an engine, an aftertreatment system with a particulate filter, and a controller. The controller is configured to compare a time value since a last delta pressure soot load estimate process to a predetermined time threshold. Responsive to the time value being greater than or equal to the predetermined time threshold, the controller decreases a flow threshold value to a lower flow threshold value. If the flow amount is greater than or equal to the lower flow threshold value, then the controller activates a delta pressure soot load estimation process. A combined soot load estimate is then calculated using a delta pressure soot load estimation of the delta pressure soot load estimate process responsive to the lower flow threshold value.

Abstract: A hydraulic system comprises a fluid tank and a pump, including a pump reservoir, fluidly coupled to the tank via a supply line. A valve is in fluidic communication with the pump reservoir via a pressure line. A backflow line fluidly couples the pump reservoir to the fluid tank via a timer reservoir and an orifice included in the timer reservoir. The hydraulic system transitions between a normal state and a purge state. In the normal state in which the pump is on, a first portion of the fluid is communicated from the pump reservoir to the valve and a second portion of the fluid is communicated from the pump reservoir to the tank. In the purge state, the pressure line and valve are purged followed by the backflow line and the pump reservoir such that no fluid remains in the pump reservoir.

Abstract: An aftertreatment system can include a radiation shield for reducing and/or redirecting radiative thermal energy. The aftertreatment system can include a first housing, a second housing, a first aftertreatment component, and the radiation shield. The first aftertreatment component is positioned within one of a first interior volume of the first housing or a second interior volume of the second housing. The radiation shield includes an attachment portion and a thermal barrier portion. The attachment portion is coupled to an exterior of the first housing or the second housing. The thermal barrier portion is structured to divert radiative thermal energy in a second direction different than a source direction of the radiative thermal energy.

Abstract: A mixing assembly for an exhaust aftertreatment system includes a mixing body, an upstream plate, a downstream plate, and a swirl plate. The mixing body includes an upstream mixing body opening and a downstream mixing body opening. The upstream mixing body opening is configured to receive exhaust gas. The upstream plate is coupled to the mixing body. The upstream plate includes a plurality of upstream plate openings. Each of the plurality of upstream plate openings is configured to receive a flow percentage that is less than 50% of the total flow of the exhaust gas. The downstream plate is coupled to the mixing body downstream from the upstream plate in a direction of exhaust gas flow. The downstream plate includes a downstream plate opening. The swirl plate is positioned between the upstream plate and the downstream plate and defines a swirl collection region and a swirl concentration region.