An exhaust gas treatment system includes an exhaust gas pathway configured to receive exhaust gas from an internal combustion engine. The exhaust gas treatment system further includes a treatment element configured to reduce an emissions component of the exhaust gas, and a sample collector positioned within the exhaust gas pathway downstream of the treatment element. The sample collector includes a plurality of inlet openings spaced about a periphery of the exhaust gas pathway and configured to receive a sample of exhaust gas from the exhaust gas pathway, and an outlet in fluid communication with the plurality of inlet openings. A sensor located at the outlet of the sample collector is configured to measure a characteristic of the sample.

The subject matter of the present invention relates to trained machine-learning models (300), methods (200, 400) and apparatuses (500) allowing a future resonant frequency of a catalyst for selective reduction of nitrogen oxides (SCR) to be predicted, the resonant frequency being representative of a concentration of a reducing agent within the SCR. The SCR forms part of a system for after-treatment of a flow of exhaust gases of an internal combustion engine with which a motor vehicle is provided. The general principle of the invention is based on the observation of correlations between the resonant frequency of an SCR and the concentration of ammonia present within the SCR. This observation led the inventor to envision using machine learning to create a trained machine-learning model in order to predict the resonant frequency of an SCR. In the invention, the trained machine-learning model is a so-called predictive model in which significant correlations are discovered in a set of past observations and in which it is sought to generalize these correlations to cases that have not yet been observed.

An aftertreatment system for treating an exhaust gas comprises an exhaust conduit, a preheating oxidation catalyst, a primary oxidation catalyst disposed downstream of the preheating oxidation catalyst, and a selective catalytic reduction system disposed in the exhaust conduit downstream of the primary oxidation catalyst. A controller is configured to determine a temperature of an exhaust gas at an inlet of the selective catalytic reduction system. In response to the temperature being below a threshold temperature, the controller generates a hydrocarbon insertion signal configured to cause hydrocarbons to be inserted into or upstream of the preheating oxidation catalyst so as to increase a temperature of the exhaust gas to above the threshold temperature.

Fluid assembly for use in a fluid system, having a control module including a processing unit for processing control commands into individual electrical control signals with individually adjustable control signal levels and a control signal level electrically connected to the processing unit, with a power unit, which has a power module for converting the control signals into individual electrical control currents as a function of the control signal levels and an output interface electrically connected to the power module, wherein the processing unit is designed to provide a first group of control signals in a first time interval which can be individually predetermined for each control signal and to provide a second group of control signals in a second time interval which can be individually predetermined for each control signal and follows the respective first time interval, wherein the first control signal and the second control signal are selected in such a way that the control currents in the first time interval are greater than the control currents in the second time interval.

A heavy duty truck includes a diesel engine that generates an exhaust gas flow and an exhaust after-treatment system for treatment of the exhaust gas flow. The exhaust after-treatment system includes at least one temperature sensor at an underbody SCR system within the exhaust after-treatment system and a DEF injector upstream of a close-coupled SCR system within the exhaust after-treatment system. The DEF injector is operated to inject DEF into the exhaust gas flow at a rate that varies as a function of a temperature measured by the temperature sensor.

A Diesel Emissions Fluid (DEF) Thawing arrangement is provided for use with a vehicle having an engine, an Engine Control Module (ECM), an exhaust system, and an SCR catalytic device. A DEF injection system is connected to the exhaust system and to the ECM. A DEF tank is connected to the DEF injection system. An exhaust pipe branch is connected to the exhaust system. A heat exchanging apparatus is connected to the exhaust pipe branch and is configured to exchange heat from exhaust gas within the exhaust pipe branch to the DEF in the DEF tank. The heat exchanging apparatus may be an exhaust gas to DEF heat exchanger located at least partially within the DEF tank, or may be an exhaust gas to coolant heat exchanger connected to an engine coolant circuit and a coolant to DEF heat exchanger located at least partially within the DEF tank.

Methods and systems are provided for adjusting an ammonia (NH.sub.3) sensor output using readings of a nitrogen oxide (NOx) sensor, the NOx sensor having a sensitivity factor to NH.sub.3. In one example, a method may include determining and updating a gain value of the NH.sub.3 sensor during zero NOx conditions to be used to calculate a corrected NH.sub.3 sensor output value, and determining and updating an offset value of the NH.sub.3 sensor during zero NH.sub.3 conditions to be used to zero the NH.sub.3 sensor during zero NOx conditions.

An apparatus for a gas turbine power plant that uniquely configures emission control equipment such that the plant can extend the emissions compliant operational range, the apparatus including a plurality of oxidation (CO) catalysts arranged in series.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.

Disclosed is a method for heating a housing containing at least one functional member, the housing including: at least one wall shared with a reservoir intended to receive a liquid; and at least one wall provided with an orifice leading to the outside and closed by a pressure equalizing membrane porous to water vapor and impermeable to liquid water. The method is notable in that the interior volume of the housing is heated in at least one of the following situations: when the reservoir is subjected to a drop in temperature other than a drop in temperature likely to cause the liquid to freeze; each time a vehicle equipped with this housing is started; and when thermal conditions capable of producing condensates are detected in the interior volume of the housing, closed by the membrane.