Abstract: Exhaust systems are described. In examples, an exhaust flow path couples exhaust ports with one or more turbochargers of an engine. The exhaust flow path may have a portion flowing through a cylinder head (e.g., couplable to the exhaust ports) and a portion flowing through an exhaust manifold (couplable to the cylinder head and the turbocharger(s)). The flow paths may be shaped to reduce the sharpness of turns between the exhaust ports and the turbocharger(s). For example, curves along the flow path may be less than 90 degrees or have a minimum curve radius, which may vary along the flow path. Additionally, at least two, independent flow paths may exist between the exhaust ports and the turbocharger(s). The cross-sectional shape of any part of the flow path may be elliptical, including at inlets and outlets.

Abstract: Exhaust systems are described. In examples, an exhaust flow path couples exhaust ports with one or more turbochargers of an engine. The exhaust flow path may have a portion flowing through a cylinder head (e.g., couplable to the exhaust ports) and a portion flowing through an exhaust manifold (couplable to the cylinder head and the turbocharger(s)). The flow paths may be shaped to reduce the sharpness of turns between the exhaust ports and the turbocharger(s). For example, curves along the flow path may be less than 90 degrees or have a minimum curve radius, which may vary along the flow path. Additionally, at least two, independent flow paths may exist between the exhaust ports and the turbocharger(s). The cross-sectional shape of any part of the flow path may be elliptical, including at inlets and outlets.

Abstract: Exhaust systems are described. In examples, an exhaust flow path couples exhaust ports with one or more turbochargers of an engine. The exhaust flow path may have a portion flowing through a cylinder head (e.g., couplable to the exhaust ports) and a portion flowing through an exhaust manifold (couplable to the cylinder head and the turbocharger(s)). The flow paths may be shaped to reduce the sharpness of turns between the exhaust ports and the turbocharger(s). For example, curves along the flow path may be less than 90 degrees or have a minimum curve radius, which may vary along the flow path. Additionally, at least two, independent flow paths may exist between the exhaust ports and the turbocharger(s). The cross-sectional shape of any part of the flow path may be elliptical, including at inlets and outlets.

Abstract: In a method of regenerating a NOx adsorber, the NOx adsorber is used to treat exhaust gases created during the combustion of gaseous fuels in general. Methane is introduced into a reformer or exhaust line in which hydrogen generated during reforming is used to regenerate the NOx absorber.

Abstract: In a method of regenerating a NOx adsorber, the NOx adsorber is used to treat exhaust gases created during the combustion of gaseous fuels in general. Methane is introduced into a reformer or exhaust line in which hydrogen generated during reforming is used to regenerate the NOx absorber.

Abstract: A method and apparatus create an environment within a combustion chamber of an internal combustion engine suitable for auto-ignition and combustion of a fuel that will not otherwise auto-ignite. Under high-load conditions, a pilot quantity of the fuel is injected in the combustion chamber of an internal combustion engine during the compression stroke of the piston. The quantity and timing of the fuel are chosen to heat an intake charge within the combustion chamber to a temperature at or above the auto-ignition temperature of the fuel by the time required for a main injection of the fuel to drive the piston during the power stroke. Generally, auto-ignition temperatures should be reached at or near top dead center of the piston. An injector design delivers fuel in manner carried out by the method.

Abstract: A method and apparatus manage heat in exhaust gas in an aftertreatment system that employs a lean NOx adsorber. A de-sulfation hot line and cooling line are employed to control exhaust gas temperatures for adsorption, regeneration and de-sulfation cycles of the aftertreatment system where each cycle can require different chemical and exhaust gas temperatures independent of the engine operation. The method and apparatus include a SOx adsorber to provide greater system durability.

Abstract: In a method of regenerating a NOx adsorber, the NOx adsorber is used to treat exhaust gases created during the combustion of gaseous fuels in general. Methane is introduced into a reformer or exhaust line in which hydrogen generated during reforming is used to regenerate the NOx absorber.

Abstract: A method and apparatus create an environment within a combustion chamber of an internal combustion engine suitable for auto-ignition and combustion of a fuel that will not otherwise auto-ignite. Under high-load conditions, a pilot quantity of the fuel is injected in the combustion chamber of an internal combustion engine during the compression stroke of the piston. The quantity and timing of the fuel are chosen to heat an intake charge within the combustion chamber to a temperature at or above the auto-ignition temperature of the fuel by the time required for a main injection of the fuel to drive the piston during the power stroke. Generally, auto-ignition temperatures should be reached at or near top dead center of the piston. An injector design delivers fuel in manner carried out by the method.

Abstract: In a method and apparatus for regenerating a lean NOx adsorber, the NOx adsorber treats exhaust gases created during the combustion of gaseous fuels in general. A bypass line maintains a target regeneration flow of exhaust gas through the NOx adsorber during regeneration regardless of operating demands on the engine. Closed-loop and open-loop control are employed. The closed-loop control employs sensors that determine properties of the exhaust gas during regeneration, and the controller uses those properties to provide an efficient regeneration cycle. A regeneration map is also provided that uses creation of in-cylinder regeneration conditions for the exhaust gas in combination with in-line regeneration conditions for the exhaust gas.