Abstract: An exhaust system for an engine is disclosed. The exhaust system may have a NOx reducer located to receive exhaust from the engine, and a bypass circuit configured to selectively pass supercharged air to the NOx reducer. The exhaust system may also have a valve disposed within the bypass circuit to regulate the flow of supercharged air, and a controller in communication with the valve. The controller may be configured to move the valve to pass the supercharged air and cool the exhaust received by the NOx reducer. The controller may also be configured to move the valve to reduce the passing of the supercharged air and remove sulfur compounds from the NOx reducer.

Abstract: A method of removing sulfur from a filter system of an engine includes continuously passing an exhaust flow through a desulfation leg of the filter system during desulfation. The method also includes sensing at least one characteristic of the exhaust flow and modifying a flow rate of the exhaust flow during desulfation in response to the sensing.

Abstract: An exhaust treatment system is provided. The system may include a particulate trap configured to remove one or more types of particulate matter from an exhaust flow of an engine. The system may also include a catalyst configured to chemically alter at least one component of the exhaust flow. Further, the system may include an exhaust conduit configured to direct the exhaust flow from the engine to the particulate trap and the catalyst. In addition, the exhaust treatment system may include a heating system configured to maintain the temperature of the catalyst above a first predetermined temperature. The heating system may also be configured to periodically raise the temperature of the particulate trap above a higher, second predetermined temperature to thereby effectuate a regeneration of the particulate trap by oxidizing particulate matter accumulated in the particulate trap.

Abstract: A method of operating an internal combustion engine includes operating the engine in a first combustion mode. The method also includes switching operation of the engine to a second combustion mode. The method includes directing an exhaust stream of the engine into contact with a NOx adsorber substantially only during the operation in the second combustion mode.

Abstract: A system is provided for monitoring exhaust gas concentrations in an exhaust stream from an engine. The system may include the exhaust system configured to carry an exhaust stream generated by the engine. The system may further include at least one sensor in communication with the exhaust stream and configured to generate an output indicative of a concentration of NOx and a concentration of at least one sulfur-containing compound in the exhaust stream. The system may further include a controller configured to selectively produce one of a rich condition and a lean condition in the exhaust stream and to determine, during the rich condition, the concentration of the at least one sulfur-containing compound in the exhaust stream based on the output from the at least one sensor and to determine, during the lean condition, the concentration of NOx in the exhaust stream based on the output from the at least one sensor.

Abstract: A diesel particulate filter includes a honeycomb structure having a plurality of elongated cell walls defining a plurality of passages and a skin layer surrounding the honeycomb structure. The filter is regenerated by oxidizing particulate matter trapped within the honeycomb structure by heating at least a portion of the honeycomb structure. A thermal gradient between the honeycomb structure and the skin layer is limited to less than a crack causing thermal gradient by utilizing at least one of maintaining a ratio of a heat capacity of the skin layer to a heat capacity of the cell walls at less than about 5, blocking at least those passages comprising a perimeter of the honeycomb structure, and heating the skin layer from an external side.

Abstract: A power system includes an engine that has engine controls, a power load, and a torque converter connected between the engine and the power load. The engine controls may operate the engine according to a first control strategy in at least some circumstances. The first control strategy may provide higher engine fuel efficiency at a first combination of engine speed and torque that corresponds to a drive speed/reaction torque band of the torque converter than it provides at combinations of engine speed and torque that do not correspond to the drive speed/reaction torque band of the torque converter. Additionally, at one or more combinations of engine speed and torque other than the first combination, the first control strategy may cause the engine to produce a lower quantity of at least one noxious exhaust emission than the engine produces at the first combination of engine speed and torque when operated according to the first control strategy.

Abstract: An exhaust system for an engine is disclosed. The exhaust system may have a NOx reducer located to receive exhaust from the engine, and a bypass circuit configured to selectively pass supercharged air to the NOx reducer. The exhaust system may also have a valve disposed within the bypass circuit to regulate the flow of supercharged air, and a controller in communication with the valve. The controller may be configured to move the valve to pass the supercharged air and cool the exhaust received by the NOx reducer. The controller may also be configured to move the valve to reduce the passing of the supercharged air and remove sulfur compounds from the NOx reducer.

Abstract: A method of regenerating a particulate filter is disclosed. The method involves heating the particulate filter to an intermediate temperature, and maintaining the particulate filter at the intermediate temperature until substantial temperature equilibrium is reached. The particulate filter is then heated to a regeneration temperature higher than the intermediate temperature.

Abstract: A power system is provided having a power source operationally coupled to a generator. The power system also includes an exhaust passage having at least one after-treatment device configured to release exhaust from the power source into the atmosphere. In addition, a controller is configured to determine at least one exhaust passage condition indicative of an exhaust temperature and operate the generator in response to the determination.

Abstract: A particulate filter regeneration system is provided for regenerating a filter at low vehicular speeds. The power source is selectively coupled to a transmission unit so that the transmission unit can be at least partially decoupled from the power source. An exhaust passage having a particulate filtering device is configured to release exhaust from the power source into the atmosphere. In addition, a controller is configured to determine at least one power source parameter indicative of an exhaust temperature, at least partially decouple the power source from the transmission unit in response to the determination, and increase a power source speed in response to the determination.

Abstract: A method is provided for operating a regeneration assembly to regenerate a filter assembly during a regeneration cycle, and for supplying fuel to at least one fuel injector unit associated with the regeneration assembly during the regeneration cycle. The method includes dispensing a cleaning substance into a fluid flow path associated with the regeneration assembly during a cleaning cycle. The method further includes directing the cleaning substance through the at least one fuel injector unit during the cleaning cycle.

Abstract: An exhaust treatment system is provided. The system may include a particulate trap configured to remove one or more types of particulate matter from an exhaust flow of an engine. The system may also include a catalyst configured to chemically alter at least one component of the exhaust flow. Further, the system may include an exhaust conduit configured to direct the exhaust flow from the engine to the particulate trap and the catalyst. In addition, the exhaust treatment system may include a heating system configured to maintain the temperature of the catalyst above a first predetermined temperature. The heating system may also be configured to periodically raise the temperature of the particulate trap above a higher, second predetermined temperature to thereby effectuate a regeneration of the particulate trap by oxidizing particulate matter accumulated in the particulate trap.

Abstract: An engine and a method of operating an internal combustion engine is provided. The method comprises supplying a pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, operating an air intake valve to open the air intake port to allow the pressurized air and exhaust gas mixture to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston, and operating the engine in an HCCI combustion mode. In at least some embodiments, a mixture of pressurized air and recirculated exhaust gas is supplied from an intake manifold to an air intake port of a combustion chamber in the cylinder. In some embodiments, the method further comprises causing an exhaust stream of an engine to contact a NOx adsorber.

Abstract: A method of operating an internal combustion engine, including at least one cylinder and a piston slidable in the cylinder, may include supplying a mixture of pressurized air and recirculated exhaust gas from an intake manifold to an air intake port of a combustion chamber in the cylinder, selectively operating an air intake valve to open the air intake port to allow pressurized air to flow between the combustion chamber and the intake manifold substantially during a majority portion of a compression stroke of the piston, and operably controlling a fuel supply system to inject fuel into the combustion chamber after the intake valve is closed.

Abstract: A filter system includes a plurality of filter sections, each of the plurality of filter sections receiving a portion of flow. Each filter section includes a first filter, a second filter, an absorbing material disposed between the first and second filter, and at least one dispersion mechanism disposed between the first and second filter. The at least one dispersion mechanism assists in providing a fluid to the filter system.

Abstract: New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.

Abstract: New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.

Abstract: A method of removing sulfur from a filter system of an engine includes continuously passing an exhaust flow through a desulfation leg of the filter system during desulfation. The method also includes sensing at least one characteristic of the exhaust flow and modifying a flow rate of the exhaust flow during desulfation in response to the sensing.

Abstract: A system is provided for monitoring exhaust gas concentrations in an exhaust stream from an engine. The system may include the exhaust system configured to carry an exhaust stream generated by the engine. The system may further include at least one sensor in communication with the exhaust stream and configured to generate an output indicative of a concentration of NOx and a concentration of at least one sulfur-containing compound in the exhaust stream. The system may further include a controller configured to selectively produce one of a rich condition and a lean condition in the exhaust stream and to determine, during the rich condition, the concentration of the at least one sulfur-containing compound in the exhaust stream based on the output from the at least one sensor and to determine, during the lean condition, the concentration of NOx in the exhaust stream based on the output from the at least one sensor.