An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine comprises an aftertreatment component and an optical assembly. The optical assembly comprises an optical emitter configured to emit light onto a face of the aftertreatment component, and an optical detector configured to detect light reflected from the face of the aftertreatment component. A controller is configured to determine at least one of an amount of NOx gases or an amount of ammonia on the face of the aftertreatment component based on an optical parameter of the detected light that has reflected from the face of the aftertreatment component.

A method and system are provided with which it is possible to detect non-firing and untimely firing events in internal combustion and, if necessary, the temperature of the gas in the exhaust gas pipe. This is performed in general by measuring the speed of sound and determining the phase angle between the sender and receiver either arranged on different sides of the exhaust gas pipe or on the same side of the exhaust gas pipe. The receiver, depending on the measurement principle, can include one, two, or in special applications three receivers. Additionally, if necessary, it is possible to suppress the structure-borne sound influence on a speed of sound measurement with low cost and high stability.

A heating system includes at least one electric heater disposed within a fluid flow system and a control device that is configured to determine a temperature of the at least one electric heater based on a model, at least one fluid flow system input, and at least one heater input. The at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes at least one of a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, and combinations thereof. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

A condensate discharge system for an exhaust gas measuring device. The condensate discharge system includes a condensate separator in which a positive pressure prevails, an outflow line in which atmospheric pressure prevails, a connecting line, and an intermediate reservoir in which the positive pressure prevails. The intermediate reservoir is arranged between the condensate separator and the outflow line and is directly connected to the condensate separator via the connecting line. The intermediate reservoir includes a float valve via which a condensate is dischargeable into the outflow line.

Defect detection systems include at least one nozzle for delivering a CO.sub.2 particulate fluid to an inlet end of a plugged honeycomb body. Defects in the honeycomb, if any, are determined by monitoring CO.sub.2 particulate flow at the outlet end of the honeycomb body. Methods for detecting defects in plugged honeycomb bodies are also disclosed.

An exhaust system for an internal combustion engine, in the exhaust duct of which a sensor is arranged for determining the exhaust gas composition. Furthermore, upstream of the sensor a guide vane is arranged, which is designed to increase the flow velocity of the exhaust gas in a local flow cross-section of the exhaust duct at the height of the sensor. This makes it possible to provide sufficiently high flow velocities of the exhaust gas at the sensor.

A control system is provided for a diesel particulate filter (DPF) system of a diesel engine configured for operation in an off-highway vehicle. The control system includes a controller configured to receive a signal corresponding to a fill state of the DPF being at or above a first threshold. The controller is configured to selectively induce a parasitic load on the diesel engine to increase an operating temperature of the engine in response to receiving the signal.

A method for measuring a heat generation distribution in a honeycomb structure includes: applying a voltage to a pair of electrode layers of the honeycomb structure to bring the honeycomb structure to an electrically conductive state; measuring resistance values R.sub.n between two different points on the surface of an outer peripheral wall of the honeycomb structure; estimating a current value I.sub.n flowing between the two points using Kirchhoff's law based on each of the resistance values R.sub.n between the two different points, and calculating a heat value generated for each of the resistance values R.sub.n based on each of the resistance values R.sub.n and the current value I.sub.n; and estimating a heat generation distribution in the honeycomb structure based on both the positions at which each of the resistance values R.sub.n is measured, and the heat value calculated from each of the resistance values R.sub.n, in the honeycomb structure.

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.

A process for detecting reductant deposits includes accessing data indicative of signal output from a radiofrequency sensor positioned proximate a decomposition reactor tube; comparing the data indicative of signal output from the radiofrequency sensor to a deposit formation threshold; and activating a deposit mitigation process responsive to the data indicative of signal output from the radiofrequency sensor exceeding the deposit formation threshold.