Abstract: An internal combustion engine system is described herein. The system uses a switching rail in combination with a first fuel rail to operate the internal combustion engine of the system. The first fuel rail receives the first fuel for combustion within one or more of the combustion cylinders of the internal combustion engine. The switching rails are configured to receive either the first fuel or a second fuel. A controller is used to operate a switching valve that, depending on the position of the switching valve, routes or directs either the second fuel or the first fuel from their respective fuel tanks. In a switching condition, such as startup, shutdown, or when the second fuel is not available, the controller can use the first fuel as the alternate source of fuel provided through the switching rail.

Abstract: Operating a gaseous fuel engine includes spark-igniting gaseous hydrogen fuel and air, and propagating combustion gases of the spark-ignited mixture outwardly from a spark gap. The propagating combustion gases are impinged upon a cone surface of a piston so as to limit a flame area of the propagating combustion gases. Additional gaseous hydrogen fuel and air is ignited in the combustion cylinder by way of the propagating combustion gases to urge a piston toward a bottom-dead-center position.

Abstract: Operating a gaseous fuel engine system includes combusting a mixture containing a gaseous hydrogen fuel and air in a cylinder of an engine, varying an operating parameter of the engine to which a crown surface temperature of a piston within the cylinder is responsive, and populating a temperature model based on a value of the varied operating parameter. Operating a gaseous fuel engine system further includes operating an oil spray apparatus to spray oil onto the piston based on the populated temperature model, and maintaining the crown surface temperature of the piston between a high temperature limit and a pre-ignition mitigation temperature limit based on the operating of the oil spray apparatus. Related apparatus and control logic is also disclosed.

Abstract: Operating a gaseous fuel engine system includes controlling at least one of a delivery location, a delivery timing, or in situ mixing of a gaseous fuel with air, based on at least one engine system parameter upon the basis of which a blowby amount of a gaseous fuel to a crankcase varies. Crankcase accumulation of the gaseous fuel is maintained below a flammability limit. Related apparatus and control logic is also disclosed.

Abstract: A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

Abstract: Operating a gaseous fuel engine system includes controlling at least one of a delivery location, a delivery timing, or in situ mixing of a gaseous fuel with air, based on at least one engine system parameter upon the basis of which a blowby amount of a gaseous fuel to a crankcase varies. Crankcase accumulation of the gaseous fuel is maintained below a flammability limit. Related apparatus and control logic is also disclosed.

Abstract: An inert blanket system includes a reformer that produces hydrogen gas and carbon dioxide. The hydrogen gas is separated from the carbon dioxide. The carbon dioxide is ported to a vapor region of a tank to reduce the flammability of the gases in the vapor region of the tank. Excess carbon dioxide is ported to an overflow system designed to store the excess carbon dioxide for future use or to sequester the carbon dioxide.

Abstract: A valve bridge to operatively interface with a rocker arm and a valve, and systems, assemblies, and methods thereof can comprise: a body, of the valve bridge, having a first side and a second side opposite the first side, a first leg of the valve bridge extending from the first side of the body, a second leg of the valve bridge extending from the first side of the body, and a third leg of the valve bridge extending from the first side of the body. A first pin can extend from an end of the first leg opposite the body, and a second pin can extend from an end of the second leg opposite the body.

Abstract: A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

Abstract: Operating an engine system includes combusting a gaseous hydrogen fuel (H2) and a gaseous hydrocarbon fuel (HC) at a first substitution ratio in a cylinder in an engine, determining at least one of an H2 fueling command or an HC fueling command based on an H2 availability input and an H2 cost, and outputting the H2 fueling command and the HC fueling command to an H2 injector and an HC admission valve, respectively. Operating the engine system further includes combusting H2 and HC at a varied substitution ratio based on the H2 fueling command and the HC fueling command. At least one of the H2 fueling command or the HC fueling command may be based on a monitored CO2 exhaust level which may be used to populate a stored history of CO2 output.

Abstract: A valve bridge to operatively interface with a rocker arm and a valve, and systems, assemblies, and methods thereof can comprise: a body, of the valve bridge, having a first side and a second side opposite the first side, a first leg of the valve bridge extending from the first side of the body, a second leg of the valve bridge extending from the first side of the body, and a third leg of the valve bridge extending from the first side of the body. A first pin can extend from an end of the first leg opposite the body, and a second pin can extend from an end of the second leg opposite the body.

Abstract: Operating a gaseous fuel engine system includes spark-igniting a gaseous hydrogen fuel and air in a prechamber sparkplug to ignite a main charge containing gaseous hydrogen fuel and air in a cylinder. Operating the gaseous fuel engine system also includes determining a preignition condition and conveying cooling air to the prechamber sparkplug based on the preignition condition to limit preignition of gaseous hydrogen fuel and air in the prechamber sparkplug. Related apparatus and control logic is also disclosed.

Abstract: Operating a gaseous fuel engine includes spark-igniting gaseous hydrogen fuel and air, and propagating combustion gases of the spark-ignited mixture outwardly from a spark gap. The propagating combustion gases are impinged upon a cone surface of a piston so as to limit a flame area of the propagating combustion gases. Additional gaseous hydrogen fuel and air is ignited in the combustion cylinder by way of the propagating combustion gases to urge a piston toward a bottom-dead-center position.

Abstract: Operating a gaseous fuel engine system includes combusting a mixture containing a gaseous hydrogen fuel and air in a cylinder of an engine, varying an operating parameter of the engine to which a crown surface temperature of a piston within the cylinder is responsive, and populating a temperature model based on a value of the varied operating parameter. Operating a gaseous fuel engine system further includes operating an oil spray apparatus to spray oil onto the piston based on the populated temperature model, and maintaining the crown surface temperature of the piston between a high temperature limit and a pre-ignition mitigation temperature limit based on the operating of the oil spray apparatus. Related apparatus and control logic is also disclosed.

Abstract: A dual fuel system includes a liquid pilot fuel supply, a liquid main fuel supply, and a fuel injection apparatus. The dual fuel system further includes a fueling control unit coupled with a cylinder pressure sensor and a NOx sensor, and structured to vary, via outputting a fueling control command to a main fuel injection control valve, fuel delivery parameters each on the basis of at least one of a cylinder pressure parameter or a NOx parameter. The fueling control unit compensates via the varying fuel delivery parameters for a change to a liquid main fuel composition such as a change from a first alcohol fuel or blend to a second alcohol fuel or blend.

Abstract: A recirculation system for a power system is disclosed. The recirculation system may determine, according to a sequence for individually activating a plurality of turbochargers of an engine, that a designated turbocharger of the plurality of turbochargers is to be activated. The recirculation system may cause a recirculation valve of a recirculation line to open to increase an airflow between an intake manifold and a compressor of the designated turbocharger.

Abstract: A method of operating a dual fuel engine includes conveying intake air, and a first fuel as a vapor and as a liquid, into a combustion cylinder in an engine, and directly injecting a second fuel into the combustion cylinder to form a first combustion charge of the first fuel as a vapor and as a liquid, the second fuel, and intake air. The second fuel is ignited to initiate combustion of the first combustion charge. Operating the dual fuel engine further includes varying at least one of, a vapor proportion of the first fuel or a total proportion of the first fuel, in a subsequent combustion charge to mitigate undesired combustion. The first fuel can include a liquid alcohol fuel. The second fuel can include a liquid compression-ignition fuel. Related apparatus and control logic is also disclosed.

Abstract: An engine brake controller may obtain a performance characteristic of an engine. The engine brake controller may determine, based on the performance characteristic of the engine, that engine braking is enabled to control the engine. The engine brake controller may monitor a set of operating parameters of the engine. The engine brake controller may determine that operating values of the set of operating parameters satisfy corresponding thresholds of the set of operating parameters. The engine brake controller may determine, based on the operating values satisfying the corresponding thresholds, an engine braking configuration associated with activating engine braking of a set of cylinders of the engine. The set of cylinders may be a proper subset of a total quantity of cylinders of the engine. The engine brake controller may cause the engine braking to be applied to the set of cylinders to increase a temperature of exhaust gas from the engine.

Abstract: A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

Abstract: A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.