An engine is equipped with an engine body, a turbocharger, an exhaust gas purifier, an exhaust communication pipe. The turbocharger is connected to the engine body. The exhaust gas purifier purifies exhaust gas discharged from the turbocharger. The exhaust communication pipe connects the turbocharger with the exhaust gas purifier. The exhaust communication pipe includes: a first connection member that is connected to the turbocharger, and a second connection member that connects the first connection member with the exhaust gas purifier. A downstream end portion of the first connection member has an inner peripheral face having a cross-section of a circular shape. An upstream end portion of the first connection member has an inner peripheral face having a cross-section of an abnormal-shape that is different from the inner peripheral face of the downstream end portion.

An aftertreatment system comprises a first passageway having a first temperature and a second passageway having a second temperature different than the first temperature. A turbine is disposed downstream from the first passageway and upstream from the second passageway. The turbine is in fluidic communication with the first passageway and the second passageway. The turbine is structured to receive an exhaust gas from the first passageway, generate energy using the exhaust gas flowing through the turbine and communicate the exhaust gas to the second passageway. The aftertreatment system also includes an insertion device structured to insert an exhaust reductant into the first passageway. A selective catalytic reduction system is configured to receive the exhaust gas from the second passageway and treat the exhaust gas. The first temperature can be higher than the second temperature.

An engine system is disclosed. The engine system may have an engine having an accessory end and a drive end opposite the accessory end. The engine system may also have a turbocharger arrangement located adjacent the accessory end. The turbocharger arrangement may be configured to receive exhaust from the engine and to deliver compressed air to the air cooling arrangement. Further, the engine system may have an air cooling arrangement located adjacent the accessory end and configured to deliver fresh air to the engine. In addition, the engine system may have a mixing duct extending from the accessory end to the drive end and configured to receive the exhaust from the turbocharger arrangement. The engine system may also have an after-treatment system located adjacent the drive end. The after-treatment system may be configured to receive the exhaust from the mixing duct and to discharge the exhaust to an ambient.

An exhaust manifold is provided comprising a first log comprising a plurality of inlet segments each having a pair of inlet ports configured to receive exhaust gas from a pair of cylinders of an engine, a second log comprising a plurality of inlet segments each having a pair of inlet ports configured to receive exhaust gas from a pair of cylinders of the engine, and a collector coupled to the logs, the collector comprising a first pair of intake openings configured to receive exhaust gas from the first log, a second pair of intake openings configured to receive exhaust gas from the second log and an outlet configured to route the exhaust gas to a turbocharger, wherein the first pair of intake openings are coupled to a pair of bellows of the first log, each of the pair of bellows being coupled to an inlet segment.

An engine controller includes processing circuitry configured to execute catalyst accelerated activation control by performing a first process that maintains an open degree of a wastegate valve at a specified first open degree and then performing a second process that changes the open degree of the wastegate valve to an open degree that differs from the first open degree.

An ECM executes a catalyst early activation control at cold start of an engine such that the activation of a catalyzer is promoted by opening a WGV. Further, the ECM performs a diagnosis process of, during execution of the catalyst early activation control, repeating opening and closing of the WGV with a given period and diagnosing whether or not the WGV is stuck, based on whether or not a fluctuation component with the same period as the period of the opening and closing of the WGV is included in output from an intake manifold pressure sensor during the repetition.

Systems and apparatuses include an engine, an aftertreatment system including a catalyst, and a controller coupled to the aftertreatment system and the engine. During a warmup period for an engine, the controller determines a value regarding a mass flow rate of exhaust gas based on information received from at least one of the engine or the aftertreatment system. The controller receives a target value regarding the mass flow rate of the exhaust gas. The controller controls at least one of the engine, the aftertreatment system, or at least one component associated therewith to reach or attempt to reach the target value regarding the mass flow rate of the exhaust gas.

A prechamber assembly includes a cylinder head including a coolant cavity, a prechamber body located within the cylinder head, the prechamber body including a nozzle, and an annular sleeve radially surrounding a portion of the prechamber body. The sleeve includes a plurality of coolant inlet holes. A portion of the prechamber body is radially spaced from the sleeve to form a coolant sleeve annulus extending along a length of the prechamber body above the coolant inlet holes. The coolant cavity and the coolant sleeve annulus are in fluid communication through the plurality of coolant inlet holes.

Systems and methods for reducing heat loss to a turbocharger during cold engine starting are described. In one example, a turbocharger bypass pipe and a turbocharger turbine pipe are oriented at forty five degrees relative to a longitudinal axis of a catalyst so that a turbocharger turbine may be completely bypassed, thereby increasing the amount of energy that may be transferred to the catalyst.

An internal combustion engine system includes a combustion cylinder provided with a reciprocating piston movable between a top dead center (TDC) and a bottom dead center (BDC) within the combustion cylinder. A first outlet valve is connected to the combustion cylinder for controllably directing exhaust gas from the combustion cylinder to a first exhaust gas manifold of the internal combustion engine system. A second outlet valve is connected to the combustion cylinder for controllably directing exhaust gas from the combustion cylinder to a second exhaust gas manifold of the internal combustion engine system. A turbocharger system includes a turbine and a compressor, wherein the turbine is arranged in fluid communication with the first exhaust gas manifold. An exhaust emission control device is arranged in fluid communication with the second exhaust gas manifold.