A high-frequency resonator forming a flow passage for an air induction system, includes an outer shell having a cylindrical inner surface at a first radial distance from a centerline, and an inner shell positioned within the outer shell and forming a volume therebetween. The inner shell includes a first cylindrical outer surface positioned at a second radial distance from the centerline, the first cylindrical outer surface forming an inner surface of the volume and having a first plurality of resonator openings, and a cylindrical support structure having a second cylindrical outer surface positioned at a third radial distance from the axial centerline, and having hydrocarbon adsorber openings. The resonator includes a hydrocarbon adsorber positioned over the cylindrical support structure, such that an inner surface of the hydrocarbon adsorber is exposed to the flow passage through the hydrocarbon adsorber openings. The third radial distance is less than the first radial distance.

A high-frequency resonator forming a flow passage for an air induction system, includes an outer shell having a cylindrical inner surface at a first radial distance from a centerline, and an inner shell positioned within the outer shell and forming a volume therebetween. The inner shell includes a first cylindrical outer surface positioned at a second radial distance from the centerline, the first cylindrical outer surface forming an inner surface of the volume and having a first plurality of resonator openings, and a cylindrical support structure having a second cylindrical outer surface positioned at a third radial distance from the axial centerline, and having hydrocarbon adsorber openings. The resonator includes a hydrocarbon adsorber positioned over the cylindrical support structure, such that an inner surface of the hydrocarbon adsorber is exposed to the flow passage through the hydrocarbon adsorber openings. The third radial distance is less than the first radial distance.

The invention relates to an exhaust after treatment system with a passive NO.sub.x adsorber and a heatable SCR catalytic converter. The exhaust gas after treatment system according to the invention for an internal combustion engine comprises an exhaust pipe, a passive NO.sub.x adsorber arranged in the exhaust pipe, an injector arranged in the exhaust pipe, a mixer arranged in the exhaust pipe, an SCR catalytic converter arranged in the exhaust pipe and a heating device arranged in the exhaust pipe, wherein the heating device is set up in such a way that at exhaust gas temperatures below a start-up temperature of the SCR catalytic converter, the temperature in the SCR catalytic converter can be brought to a temperature above the start-up temperature within a period of time by means of the heating device.

A mixer assembly for a vehicle exhaust system includes an inner wall surface and a flow diverter with a flow directing surface that is spaced apart from the inner wall surface to provide an exhaust gas inlet area. The flow directing surface terminates at a distal end that is spaced apart from the inner wall surface to provide an orifice between the distal end and the inner wall surface through which exhaust gas flow accelerates and is directed to flow along the inner wall surface. A vehicle exhaust component assembly that includes the mixer and a method for mixing injected fluid spray into the mixer are also disclosed.

Systems, apparatuses, and methods include an upstream exhaust analysis circuit structured to determine a characteristic of an exhaust gas stream entering a nitrous oxide (NOx) storage catalyst; a prediction circuit structured to predict a downstream NOx concentration of an exhaust gas stream exiting the NOx storage catalyst based on a model of a NOx storage capacity or a dynamic response of the NOx storage catalyst; a downstream exhaust analysis circuit structured to determine a downstream NOx concentration of the exhaust gas stream exiting the NOx storage catalyst; and a comparison circuit structured to compare the predicted downstream NOx concentration to the determined downstream NOx concentration, and determine a health of the NOx storage catalyst based on the comparison.

Controlling exhaust after-treatment in a heavy-duty motor vehicle includes operating a diesel engine of a heavy-duty truck such that the diesel engine generates an exhaust gas flow that enters an exhaust after-treatment system of the heavy-duty truck, the exhaust after-treatment system including a selective catalytic reduction system, measuring a level of NO.sub.x gases in the exhaust gas flow downstream of the selective catalytic reduction system, and controlling a diesel exhaust fluid injector upstream of the selective catalytic reduction system to inject diesel exhaust fluid into the exhaust gas flow upstream of the selective catalytic reduction system at an injection rate that is based on the measured level of NO.sub.x gases.

An exhaust purification system of an internal combustion engine 50 comprises: an adsorbent 20 adsorbing HC and NOx in exhaust gas, a catalyst 24 removing HC and NOx, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas discharged from an engine body of the internal combustion engine to the exhaust passage, and a temperature calculating part 32 configured to calculate a temperature of the adsorbent. At the adsorbent, a desorption temperature of HC is higher than a desorption temperature of NOx. The air-fuel ratio control part is configured to make the air-fuel ratio a stoichiometric air-fuel ratio when a temperature of the adsorbent is in the vicinity of the desorption temperature of NOx, then make the air-fuel ratio leaner than the stoichiometric air-fuel ratio when the temperature of the adsorbent reaches the vicinity of the desorption temperature of HC.

An exhaust purification system of an internal combustion engine comprises an HC adsorbent 20 arranged adsorbing HC in exhaust gas, an NOx adsorbent 20 adsorbing NOx in exhaust gas, a catalyst 24 removing HC and NOx at a predetermined air-fuel ratio, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas, and an HC concentration calculating part 32 configured to calculate a concentration of HC desorbed from the HC adsorbent. A peak of a desorption temperature of HC at the HC adsorbent and a peak of a desorption temperature of NOx at the NOx adsorbent are substantially the same. The air-fuel ratio control part is configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to the predetermined air-fuel ratio based on the concentration of HC calculated by the HC concentration calculating part when HC is desorbed from the HC adsorbent.

Methods and systems are provided for monitoring a NOx storage capacity of a passive NOx adsorption catalyst (PNA) included in an exhaust gas after-treatment system of an engine. In one example, a method may include, after an engine cold start and prior to an exhaust gas temperature reaching an upper threshold temperature, indicating degradation of the PNA based on an amount of NOx measured downstream of the PNA during a fuel cut event and while the exhaust gas temperature is between a lower threshold temperature and the upper threshold temperature. In this way, degradation of the NOx storage capacity may be inferred based on an amount of NOx released from the PNA and independent of a NOx storage measurement.

The disclosure provides a monolithic wall-flow filter catalytic article including a substrate having an aspect ratio of from about 1 to about 20, and having a functional coating composition disposed on the substrate, the functional coating composition including a first sorbent composition, an oxidation catalyst composition, and optionally, a second sorbent composition. The monolithic wall-flow filter catalytic article may be in a close-coupled position close to the engine. The disclosure further provides an integrated exhaust gas treatment system including the monolithic wall-flow filter catalytic article and may additionally include a flow-through monolith catalytic article. The flow-through monolith catalytic article includes a substrate having a selective catalytic reduction (SCR) coating composition disposed thereon. The integrated exhaust gas treatment system simplifies the traditional four-article system into a two-article Catalyzed Soot Filter (CSF) plus Selective Catalytic Reduction (SCR) CSF+SCR arrangement.