Abstract: Operating an engine system includes calculating a crank angle timing term corresponding to an in-cylinder temperature sufficient for autoignition of a first fuel injected at a first injection location. Operating an engine system further includes calculating, based on the crank angle timing term, at least one of an injection amount or an injection duration, to increase the in-cylinder temperature sufficiently via burning of the first fuel to ignite a second fuel injected into a mixture of the first fuel and pressurized intake air. The first fuel may include a blend of dimethyl ether (DME), methanol (MeOH), and water. Based on expected progression of in-cylinder temperatures, and fuel injection amount and/or duration based thereon, desirable controllability of combustion phasing and/or other combustion properties may be realized.

Abstract: A probe includes a fast-scanning cyclic voltammetry electrode, a conductive wall disposed around the fast-scanning cyclic voltammetry electrode, and a wire in electronic communication with the fast-scanning cyclic voltammetry electrode. The conductive wall is grounded. Fast scanning cyclic voltammetry electrode currents are enclosed within the conductive wall. Resulting fast scanning cyclic voltammetry can have sub-?V level artifacts.

Abstract: Operating an engine system includes autoigniting a first fuel including a plurality of liquid fuels premixed with air, to trigger ignition of a direct-injected main fuel in a first engine cycle, and receiving data indicative of an undesired heat release of combustion of the first fuel. The undesired heat release may include an undesired heat release rate (HRR) modality such as a multistage combustion. Relative amounts of the plurality of the liquid fuels are varied and admitted to the cylinder in a second engine cycle, and the first fuel having the varied relative amounts autoignited to trigger ignition of the direct-injected main fuel in the second engine cycle. The undesired heat release can be limited in the second engine cycle based on the varied relative amounts of the liquid fuels. The first fuel may include a blend of dimethyl ether (DME), methanol (MeOH), and water. The direct-injected main fuel may include MeOH and water. Related apparatus and control logic is also disclosed.

Abstract: Operating an engine includes moving a piston in a combustion chamber between a bottom dead center position and a top dead center position in an engine cycle. A fuel is injected into the combustion chamber through a plurality of sets of nozzle outlets varied set-to-set with respect to outlet size and spray angle. Spray jets of the injected fuel are propagated in an impingement-limiting fuel spray pattern that is based on the set-to-set variation in outlet size and spray angle so as to limit dissipation of heat from combustion of the injected fuel to material of the engine by way of a thermal barrier coating (TBC) upon a surface of the combustion chamber.

Abstract: A fuel injector assembly for an engine. The engine includes a cylinder head defining a through-hole. The fuel injector assembly includes an insert, having a first end and a second end, configured to be received within the through-hole and coupled to the cylinder head. The insert defines a bore extending from the first end to the second end. The fuel injector assembly further includes a fuel injector including a plurality of orifices, received within the bore of the insert; and a duct structure including a plurality of ducts, coupled to the insert such that the plurality of ducts align with the plurality of orifices to at least partially receive one or more fuel jets from the plurality of orifices of the fuel injector.

Abstract: A fuel injector assembly for an engine. The engine includes a cylinder head defining a through-hole. The fuel injector assembly includes an insert, having a first end and a second end, configured to be received within the through-hole and coupled to the cylinder head. The insert defines a bore extending from the first end to the second end. The fuel injector assembly further includes a fuel injector including a plurality of orifices, received within the bore of the insert; and a duct structure including a plurality of ducts, coupled to the insert such that the plurality of ducts align with the plurality of orifices to at least partially receive one or more fuel jets from the plurality of orifices of the fuel injector.

Abstract: A system having an engine is provided. The system includes a high pressure (HP) turbocharger and a low pressure (LP) turbocharger connected in series with each other. The system also includes a first valve assembly configured to selectively bypass at least a portion of the exhaust from the engine to the LP turbocharger. The system also includes a storage tank configured to store a pressurized fluid and configured to be in fluid communication with the HP turbocharger and the LP turbocharger. The system further includes a second valve assembly in fluid communication with the storage tank, the HP turbocharger and the LP turbocharger. The system also includes a controller operatively coupled to the first valve assembly and the second valve assembly. The controller is configured to selectively operate the first valve assembly and the second valve assembly based on a change in a load requirement on the engine.

Abstract: A duct structure for a fuel injector assembly of an engine includes a first ring structure, a plurality of ducts, a plurality of posts, and an engagement structure. The fuel injector assembly includes a fuel injector having a plurality of orifices to discharge fuel. The first ring structure is configured to be coupled to a cylinder head of the engine, and defines a central axis. The ducts are circularly arrayed around the central axis, and are configured to provide passages to the fuel discharged from the fuel injector. The posts connect the ducts to the first ring structure. Further, the engagement structure is configured to engage with the fuel injector to align the ducts with the orifices such that each of the plurality of ducts is configured to receive fuel discharged from a corresponding one of the plurality of orifices.

Abstract: A thermal management system for an aftertreatment system includes an air pump and a compressed air rail. The compressed air rail is fluidly connected with the air pump. The thermal management system further includes a first valve located between the compressed air rail and an exhaust outlet pathway. The first valve is configured to selective supply air to the aftertreatment system of the engine. The thermal management system further includes a heater located between the compressed air rail and the first valve. The heater is configured to heat the air before supplying air to the aftertreatment system of the engine.

Abstract: A ducted combustion system for an internal combustion. The ducted combustion system includes a combustion chamber, a fuel injector in fluid communication with the combustion chamber and configured to inject a sequence of at least two fuel charges into a combustion chamber during a combustion cycle and one or more ducts disposed within the combustion chamber and configured to receive at least a part of the fuel charges.

Abstract: A thermal management system for an aftertreatment system includes an air pump and a compressed air rail. The compressed air rail is fluidly connected with the air pump. The thermal management system further includes a first valve located between the compressed air rail and an exhaust outlet pathway. The first valve is configured to selective supply air to the aftertreatment system of the engine. The thermal management system further includes a heater located between the compressed air rail and the first valve. The heater is configured to heat the air before supplying air to the aftertreatment system of the engine.

Abstract: An exhaust gas recirculation (EGR) system includes an EGR duct configured to effect fluid communication between an exhaust duct and an intake duct of an internal combustion engine; a heat exchanger having a first flow passage and a second flow passage, the first flow passage being in fluid communication with the EGR duct, the second flow passage being configured to receive a heat transfer medium from a heat transfer medium source; an upstream purge valve in fluid communication with the second flow passage of the heat exchanger, and configured to effect selective fluid communication between a purge fluid source and the second flow passage of the heat exchanger; and a controller operatively coupled to the upstream purge valve. The controller is configured to purge the second flow passage of the heat exchanger by opening the upstream purge valve.

Abstract: An engine system is provided. The engine system includes a first engine adapted to generate a first exhaust flow. The engine system includes a first aftertreatment unit associated with the first engine. The first aftertreatment unit receives at least a portion of the first exhaust flow therein. The engine system includes a second engine adapted to generate a second exhaust flow. The engine system also includes a second aftertreatment unit associated with the second engine. The second aftertreatment unit receives the second exhaust flow therein. The engine system further includes a distribution unit coupled to the first aftertreatment unit and the second aftertreatment unit. The distribution unit is adapted to selectively bypass a remaining portion of the first exhaust flow to the second aftertreatment unit. The remaining portion of the first exhaust flow is adapted to introduce an amount of unburned hydrocarbon (CxH2x) in to the second aftertreatment unit.

Abstract: A system having an engine is provided. The system includes a high pressure (HP) turbocharger and a low pressure (LP) turbocharger connected in series with each other. The system also includes a first valve assembly configured to selectively bypass at least a portion of the exhaust from the engine to the LP turbocharger. The system also includes a storage tank configured to store a pressurized fluid and configured to be in fluid communication with the HP turbocharger and the LP turbocharger. The system further includes a second valve assembly in fluid communication with the storage tank, the HP turbocharger and the LP turbocharger. The system also includes a controller operatively coupled to the first valve assembly and the second valve assembly. The controller is configured to selectively operate the first valve assembly and the second valve assembly based on a change in a load requirement on the engine.

Abstract: An exhaust gas recirculation (EGR) system includes an EGR duct configured to effect fluid communication between an exhaust duct and an intake duct of an internal combustion engine; a heat exchanger having a first flow passage and a second flow passage, the first flow passage being in fluid communication with the EGR duct, the second flow passage being configured to receive a heat transfer medium from a heat transfer medium source; an upstream purge valve in fluid communication with the second flow passage of the heat exchanger, and configured to effect selective fluid communication between a purge fluid source and the second flow passage of the heat exchanger; and a controller operatively coupled to the upstream purge valve. The controller is configured to purge the second flow passage of the heat exchanger by opening the upstream purge valve.

Abstract: A method for operating a hybrid powertrain includes effecting a first mixture in a combustion chamber of an internal combustion engine while the internal combustion engine operates at a first predetermined load, the first mixture being lean of stoichiometric and being substantially homogeneous throughout the combustion chamber at a first start of combustion time; effecting a second mixture in the combustion chamber while the internal combustion engine operates at a second predetermined load, the second mixture being lean of stoichiometric and being substantially homogeneous throughout the combustion chamber at a second start of combustion time; and effecting a third mixture in the combustion chamber while the internal combustion engine transitions from the first predetermined load to the second predetermined load, the third mixture including a fuel-rich region being rich of stoichiometric at a third start of combustion time.

Abstract: A fuel injection apparatus for use in a compression ignition engine comprises a first injector tip defining a first set of outlet orifices therethrough and a second injector tip defining a second set of outlet orifices therethrough. The first set of outlet orifices has a first conicity and the second set of outlet orifices has a second conicity. The first conicity is different from the second conicity.

Abstract: A purging system for an engine system is disclosed. The engine system includes an engine and one or more to-be-purged sub-systems. The purging system includes a centralized purging unit with one or more compressed air sources to store and provide compressed air. The compressed air sources are fluidly communicable with each of the to-be-purged sub-systems. A control valve assembly includes one or more valves that are operably positioned between the compressed air sources and the to-be-purged sub-systems. A controller, which is in control communication with the control valve assembly, is configured to alternate the valves between an active state and an inactive state. This is to vary the fluid communication between the compressed air sources and at least one of the to-be-purged sub-systems. This alteration is based on a set of predefined threshold conditions.