Abstract: Methods and systems are provided for maintaining combustion stability in a multi-fuel engine. In one example, a system may include first and second fuel systems to deliver liquid and gaseous fuels, respectively, to at least one cylinder of the engine, and a controller. The controller may be configured to supply the gaseous fuel to the at least one cylinder, inject the liquid fuel to the at least one cylinder to compression ignite the liquid fuel and combust the gaseous fuel in the at least one cylinder, and retard an injection timing of the injection of the liquid fuel based on a measured parameter associated with auto-ignition of end gases subsequent to the compression-ignition of the liquid fuel. In some examples, the controller may further be configured to adjust an amount of the gaseous fuel relative to an amount of the liquid fuel based on the measured parameter.

Abstract: A system and method are provided for controlling a plurality of fuel cells. The method includes coordinating a distribution of a power demand in response to a power request of a power system comprising a plurality of fuel cells, the power output of each of the fuel cells selected based on a respective efficiency of each of the fuel cells.

Abstract: A multi-fuel injector assembly in one embodiment includes a first fuel injector assembly to deliver a first type of fuel and a second fuel delivery system to deliver a second type of fuel. The first fuel injector includes a first nozzle, at least one first needle, and at least one first actuator configured to move the at least one first needle. The at least one first actuator moves the at least one first needle to a first fuel delivery configuration that corresponds to a first fuel mixture composition, and a second fuel delivery configuration that corresponds to a second fuel mixture composition.

Abstract: Various methods and systems are provided for using only hydrogen as fuel in a duel fuel engine. In one example, a method may include direct injecting only hydrogen as fuel to one or more engine cylinders and compression igniting the injected hydrogen.

Abstract: Various methods and systems are provided for skipping fire in one or more cylinders in a dual fuel engine. In one example, a method may include injecting a combination of two fuels to a first set of cylinders of the engine while disabling fuel injection to all remaining cylinders of the engine.

Abstract: An insert device includes a body having an upper body portion configured to couple with a cylinder head of an engine cylinder and a lower body portion extending from the upper body portion toward a combustion chamber of the engine cylinder. The body includes an interior surface extending around a central volume positioned to receive liquid fuel from a fuel injector. The body includes gas inlet channels and fuel-and-gas mixture outlet channels. The gas inlet channels direct gas into the central volume where the gas mixes with the liquid fuel to form the fuel-and-gas mixture. The fuel-and-gas mixture outlet channels direct the mixture into the combustion chamber. The interior surface includes concave surface portions between the inlet channels and the outlet channels along a center axis of the body that are shaped to direct the gas into the central volume toward the liquid fuel in the central volume.

Abstract: Various methods and systems are provided for a method for a hybrid engine system. In one example, the method includes operating an electrical turbocharger to modify engine operating efficiency and to extend battery charge over a duration of a travel route based on a real-time status of the battery charge. The method allows fuel consumption to be decreased while meeting power demands of vehicle navigation.

Abstract: A turbine-compressor assembly includes a turbine-compressor device fluidly coupled with a heat source, a compressor, and a turbine via plural valves. A power device is coupled with the turbine-compressor device via a shaft. A controller can control operation of the plural valves to control the movement of fluids within the assembly to selectively switch between the turbine-compressor device operating in one of plural operating modes. In a first mode of operation, the turbine-compressor device can generate electrical power and direct the electrical power to the power device to control an amount of power provided to or extracted from the shaft by the power device. In a second mode of operation, the turbine-compressor device can receive electrical power from the power device to consumer the electrical power.

Abstract: An alignment system includes an optical sensor device that may be inserted into a passage of a body that is located between a fuel injector and a combustion chamber of an engine cylinder. The body is shaped to transmit fuel ejected from a spray hole in a fuel injector into the combustion chamber of the engine cylinder. The system also includes a controller that may examine output of the optical sensor device and determine whether the passage of the body is aligned with the spray hole of the fuel injector based on the output from the optical sensor device. The controller may change a position of one or more of the body or the fuel injector responsive to determining that the passage of the body is not aligned with the spray hole of the fuel injector.

Abstract: Various methods and systems are provided for engine startup. In one example, a method for an engine includes injecting a fuel mixture with a proportion of a first fuel to a second fuel to decrease carbon emissions, in response to detection of or request for the engine to start. The proportion of the first fuel to the second fuel in the injected fuel mixture is decreased in response to engine speed reaching an idling speed. The first fuel may be a non-hydrocarbon-based fuel and the second fuel may be a hydrocarbon-based fuel.

Abstract: An engine control unit of a multi-fuel is provided. The engine consumes a mixture of a first combustion fuel and a second combustion fuel. The engine control unit includes hardware circuitry that includes one or more processors configured to calculate an autoignition delay of the mixture of the air and the second combustion fuel based on current operating conditions of the multi-fuel engine. The one or more processors also are configured to calculate an upper limit on an amount of the second combustion fuel that is supplied to the multi-fuel engine based on the autoignition delay that is calculated.

Abstract: An insert device may include a body coupled with an engine cylinder head. The body has an interior surface shaped to receive and engage a distal tip of a fuel injector. The body has gas conduits and mixture conduits with gas conduits extending from inlets along an exterior surface to outlets that intersect the mixture conduits. The mixture conduits extend from inlets along an interior surface of the body to outlets on the exterior surface. The gas conduits are positioned to direct gases outside of the body into the mixture conduits. The mixture conduits are positioned to receive fuel from spray holes of the fuel injector. The mixture conduits can entrain the gas with the fuel into a fuel-and-gas mixture that is directed out of the outlets of the mixture conduits and into a combustion chamber of an engine cylinder.

Abstract: A vehicle control system and a method of operating thereof may include determining a first ratio at which to operate a vehicle system at a first location along a route along which the vehicle system moves. The first ratio may be based on an amount of a first fuel of a first fuel source relative to an amount of a second fuel of a second fuel source. The vehicle system may be powered by one or more of the first or the second fuel sources. First operational settings at which to control the vehicle system may be determined based on the first ratio between the first and second fuel sources at the first location along the route. Operation of the vehicle system may be controlled according to the first operational settings to move the vehicle system according to the first ratio at the first location along the route.

Abstract: Various methods and systems are provided for energy management at a consist. In one example, a method for the energy management includes coordinating a distribution of a power demand in response to a power output of each of a fuel cell system, a battery system, and an engine system. The power output of each of the fuel cell system, the battery system, and the engine system may be selected based on a respective efficiency of each system.

Abstract: Methods and systems are provided for a multi-fuel engine. In one example, a method includes adjusting a substitution ratio based on an intake manifold temperature. The method further including adjusting the intake manifold temperature to increase the substitution ratio.

Abstract: Various methods and systems are provided for venting fuel lines in a dual-fuel engine. In one example, a method may include in response to an engine shut-down request, venting fuel lines to remove hydrogen from the fuel lines.

Abstract: A method and a turbine-compressor assembly of a system having a turbine-compressor device fluidly coupled with a heat source, a compressor, and a turbine via plural valves. A power device may be coupled with the turbine-compressor device. A controller may control operation of the plural valves to control movement of fluids within the assembly to selectively switch between the turbine-compressor device operating in one of plural modes. In a turbine mode of operation, the turbine-compressor device may generate electrical power and direct the electrical power to the power device. In a compressor mode of operation, the turbine-compressor device may receive electrical power from the power device to consume the electrical power.

Abstract: Various methods and systems are provided for using only hydrogen as fuel in a duel fuel engine. In one example, a method may include direct injecting only hydrogen as fuel to one or more engine cylinders and compression igniting the injected hydrogen.

Abstract: Various methods and systems are provided for skipping fire in one or more cylinders in a dual fuel engine. In one example, a method may include injecting a combination of two fuels to a first set of cylinders of the engine while disabling fuel injection to all remaining cylinders of the engine.

Abstract: Methods and systems are provided for a multi-fuel engine. In one example, a method includes adjusting an ignitability of a combustion mixture comprising ammonia and hydrogen. The combustion mixture may further include a carbon-containing fuel.