Abstract: Methods and systems are provided for an exhaust system. In one example, a method includes heating an aftertreatment device during an engine off. The heating includes utilizing one or more of an injector, a heater, and a recirculation fan.

Abstract: An exhaust aftertreatment device includes a catalyst assembly having an electrically conductive carrier matrix and first and second electrodes. The first and second electrodes have terminals attached on opposing sides of the catalyst assembly to be electrically connected to each other through the carrier matrix and configured to generate heat. A first elongate heat sink extends axially along the first electrode and is configured to absorb a portion of the heat to mitigate formation of hotspots.

Abstract: Methods and systems are provided for an exhaust system. In one example, a method includes heating an aftertreatment device during an engine off. The heating includes utilizing one or more of an injector, a heater, and a recirculation fan.

Abstract: Methods and systems are provided for filtering particulate matter in an exhaust passage of an engine system. In one example, a method may include during a cold start condition comprising an engine temperature being less than a threshold engine temperature, directing engine exhaust gas to an exhaust particulate filter, and during a warm engine condition, directing engine exhaust gas to bypass the exhaust particulate filter, wherein the warm engine condition comprises the engine temperature being greater than or equal to the threshold engine temperature and fuel being combusted in the engine. In this way, the exhaust particulate filter may be reliably regenerated during engine shutdown events such as DFSOs while reducing filter degradation, and lowering PM emissions.

Abstract: Methods and systems are provided for a steam reforming catalyst. In one example, a method may include flowing exhaust gas from a first cylinder bank directly to a three-way catalyst, flowing exhaust gas from a second cylinder bank directly to a steam reforming catalyst, and flowing exhaust gas from the steam reforming catalyst to the three-way catalyst.

Abstract: Methods and systems are provided for a steam reforming catalyst. In one example, a method may include flowing exhaust gas from a first cylinder bank directly to a three-way catalyst, flowing exhaust gas from a second cylinder bank directly to a steam reforming catalyst, and flowing exhaust gas from the steam reforming catalyst to the three-way catalyst.

Abstract: Methods and systems are provided for filtering particulate matter in an exhaust passage of an engine system. In one example, a method may include during a cold start condition comprising an engine temperature being less than a threshold engine temperature, directing engine exhaust gas to an exhaust particulate filter, and during a warm engine condition, directing engine exhaust gas to bypass the exhaust particulate filter, wherein the warm engine condition comprises the engine temperature being greater than or equal to the threshold engine temperature and fuel being combusted in the engine. In this way, the exhaust particulate filter may be reliably regenerated during engine shutdown events such as DFSOs while reducing filter degradation, and lowering PM emissions.

Abstract: Methods and systems are provided for filtering particulate matter in an exhaust passage of an engine system. In one example, a method may include during a cold start condition comprising an engine temperature being less than a threshold engine temperature, directing engine exhaust gas to an exhaust particulate filter, and during a warm engine condition, directing engine exhaust gas to bypass the exhaust particulate filter, wherein the warm engine condition comprises the engine temperature being greater than or equal to the threshold engine temperature and fuel being combusted in the engine. In this way, the exhaust particulate filter may be reliably regenerated during engine shutdown events such as DFSOs while reducing filter degradation, and lowering PM emissions.

Abstract: Phosphorus tolerant or resistant three-way catalysts (TWC) are disclosed. The TWC may include a substrate defining a plurality of channels. It may include front and rear washcoat portions overlying the substrate and having respective first and second washcoat loadings, the first washcoat loading being at most 2.0 g/in3 and less than the second washcoat loading. The front washcoat portion may include a catalyst material supported on a support material comprising a cerium oxide, such as ceria or CZO, or a pre-phosphated material, such as AlPO4, or CePO4. In one embodiment, the support material may comprise at least 85 wt. % of a cerium oxide or at least 85 wt. % of a phosphate-containing material. The front portion and the underlying substrate may comprise from 3 to 25 vol. % of the three-way catalyst or the front portion may overly up to an initial 15% of an axial length of the substrate.

Abstract: Phosphorus tolerant or resistant three-way catalysts (TWC) are disclosed. The TWC may include a substrate defining a plurality of channels. It may include front and rear washcoat portions overlying the substrate and having respective first and second washcoat loadings, the first washcoat loading being at most 2.0 g/in3 and less than the second washcoat loading. The front washcoat portion may include a catalyst material supported on a support material comprising a cerium oxide, such as ceria or CZO, or a pre-phosphated material, such as AlPO4, or CePO4. In one embodiment, the support material may comprise at least 85 wt. % of a cerium oxide or at least 85 wt. % of a phosphate-containing material. The front portion and the underlying substrate may comprise from 3 to 25 vol. % of the three-way catalyst or the front portion may overly up to an initial 15% of an axial length of the substrate.

Abstract: Methods and systems are provided for filtering particulate matter in an exhaust passage of an engine system. In one example, a method may include during a cold start condition comprising an engine temperature being less than a threshold engine temperature, directing engine exhaust gas to an exhaust particulate filter, and during a warm engine condition, directing engine exhaust gas to bypass the exhaust particulate filter, wherein the warm engine condition comprises the engine temperature being greater than or equal to the threshold engine temperature and fuel being combusted in the engine. In this way, the exhaust particulate filter may be reliably regenerated during engine shutdown events such as DFSOs while reducing filter degradation, and lowering PM emissions.

Abstract: A motor-vehicle engine system comprises a first DOC configured to receive exhaust from an engine and an SCR device coupled downstream of the first DOC in a flow direction of the exhaust. The system further comprises a second DOC coupled downstream of the SCR device. The system takes advantage of hydrocarbon sorption in the SCR catalyst that is a function of temperature to enable reduced hydrocarbon emissions via oxidation at the second DOC.

Abstract: Embodiments for heating an emission control device are provided. In one example, a method for a turbocharged engine comprises during an engine cold-start, delivering boosted air from downstream of a compressor into a wastegate duct coupled across a turbine and exothermically reacting a reductant with the boosted air upstream of an exhaust emission control device. In this way, boosted air may be used to initiate an exothermic reaction to heat the device.

Abstract: Methods and systems are provided for heating a catalyst during engine cold-start conditions. One example embodiment uses positive valve overlap to drive a boosted blow-through airflow through the cylinders of an engine. Fuel is injected with the blow-through airflow during the valve overlap, and also injected into engine cylinders outside the valve overlap. The catalyst is heated by the resulting exothermic reaction of the blow-through airflow with the combustion products and the injected fuel in the exhaust manifold.

Abstract: A vehicle system operation method is provided. The method comprises, during a first operating condition, increasing back pressure in a first exhaust conduit positioned upstream of a turbine and downstream of a first emission control device and during a second operating condition, reducing back pressure in the first exhaust conduit and flowing boosted air from downstream of a compressor into a second exhaust conduit positioned upstream of a second emission control device and downstream of the turbine.

Abstract: A vehicle system operation method is provided. The method comprises, during a first operating condition, increasing back pressure in a first exhaust conduit positioned upstream of a turbine and downstream of a first emission control device and during a second operating condition, reducing back pressure in the first exhaust conduit and flowing boosted air from downstream of a compressor into a second exhaust conduit positioned upstream of a second emission control device and downstream of the turbine.

Abstract: Embodiments for heating an emission control device are provided. In one example, a method for a turbocharged engine comprises during an engine cold-start, delivering boosted air from downstream of a compressor into a wastegate duct coupled across a turbine and exothermically reacting a reductant with the boosted air upstream of an exhaust emission control device. In this way, boosted air may be used to initiate an exothermic reaction to heat the device.

Abstract: Methods and systems are provided for heating a catalyst during engine cold-start conditions. One example embodiment uses positive valve overlap to drive a boosted blow-through airflow through the cylinders of an engine. Fuel is injected with the blow-through airflow during the valve overlap, and also injected into engine cylinders outside the valve overlap. The catalyst is heated by the resulting exothermic reaction of the blow-through airflow with the combustion products and the injected fuel in the exhaust manifold.

Abstract: Methods and systems are provided for heating a catalyst during engine cold-start conditions. One example embodiment uses positive valve overlap to drive a boosted blow-through airflow through the cylinders of an engine. Fuel is injected with the blow-through airflow during the valve overlap, and also injected into engine cylinders outside the valve overlap. The catalyst is heated by the resulting exothermic reaction of the blow-through airflow with the combustion products and the injected fuel in the exhaust manifold.

Abstract: Systems and methods for reducing NOx emissions using a branched exhaust system with a first and second turbine including an emission-control device containing a zeolite, are described. In one example approach, a method comprises: during a first duration when exhaust temperature is below a first temperature threshold, directing exhaust gas through the second turbine and the emission-control device, and adjusting the second turbine to control intake boost; and during a second duration following the first, directing exhaust gas through the first turbine, and adjusting the first turbine to control intake boost. In this way, the first and second turbines may provide a greater degree of boost control in order to reduce boost fluctuations while enabling storing cold start NOx emissions for later reduction.