Abstract: Methods and systems are provided for a multi-fuel engine. In one example, a method includes increasing a temperature reducing mass of a combustion mixture during a transition to multi-fuel combustion from single-fuel combustion.

Abstract: Methods and systems are provided for adjusting a location of a fuel injection in response to a substitution rate and a desired EGR flow. In one example, a method may include injecting a first fuel to a combustion chamber via a direct injector positioned to inject directly into the combustion chamber, injecting a second, different, fuel to the combustion chamber via an exhaust port injector positioned to inject toward an exhaust valve of the combustion chamber, and combusting the first and second fuels together in the combustion chamber.

Abstract: Various methods and systems are provided for controlling air flow through an engine by adjusting an electric turbocharger of a vehicle. In one embodiment, a system for a vehicle comprises an electric turbocharger comprising a compressor, an exhaust turbine coupled to the compressor via a shaft, and an electric machine mechanically coupled to the shaft; and a controller including a processor and instructions stored on a non-transient memory of the controller that, when executed, cause the controller to: adjust an amount of power provided to or extracted from the shaft by the electric machine based on at least one of a speed of the electric turbocharger, a cylinder pressure, and an exhaust gas temperature. By adjusting the amount of power provided to or extracted from the electric machine, the exhaust gas temperature and the speed of the electric turbocharger may be efficiently maintained within a desired operating range.

Abstract: A method and system are provided for adjusting a speed of a turbocharger compressor using an electric motor in response to a relative substitution rate of first and second fuels in a multi-fuel engine.

Abstract: Methods and systems are provided for adjusting a substitution ratio based on water in a combustion mixture of a multi-fuel engine. In one example, a method includes adjusting a substitution ratio in response to an amount of water provided to a multi-fuel engine configured to combust a first fuel and a second fuel, the second fuel different than the first fuel.

Abstract: Various methods and systems are provided for a method for a multi-pressure fueling system. In one example, the multi-pressure fueling system includes providing a first fuel delivery pressure enabling high pressure direct injection of a fuel at a first injector and a second fuel delivery pressure insufficient for high pressure direct injection, at a second injector, based on engine operation.

Abstract: A method and system are provided for adjusting a speed of a turbocharger compressor using an electric motor in response to a relative substitution rate of first and second fuels in a multi-fuel engine.

Abstract: Methods and systems are proposed for controlling a temperature of exhaust gases generated by the engine by operating an E-Turbo of the vehicle. In one embodiment, a method is provided, comprising increasing a power generated by an electric machine mechanically coupled with an exhaust turbine of an E-Turbo of a vehicle or adjusting an engine power based on a speed of the exhaust turbine and an air-fuel ratio (AFR) of an engine of the vehicle of the engine responsive to the speed of the exhaust turbine increasing above a threshold turbine speed. By increasing or decreasing the power generated by the electric machine and/or adjusting the engine power, the temperature of the exhaust gas may be maintained within a threshold temperature range where an efficiency of an aftertreatment system may be maximized, thereby reducing an emissions of the vehicle.

Abstract: A computer-implemented method for multi-mode operation of a combustion system, a combustion system, and a heat engine are provided. The method includes initializing combustion of a fuel/oxidizer mixture, determining whether conditions at the combustion system meet or exceed a first threshold operating parameter, transitioning to detonation combustion of the fuel/oxidizer mixture if conditions at the combustion system meet or exceed the first threshold operating parameter, and maintaining or increasing fuel flow through a deflagrative fuel circuit if conditions at the combustion system do not meet or exceed the first threshold operating parameter.

Abstract: A mixing structure can include a body having first conduits, mixture conduits, and second conduits extending through the body to the internal volume. The first conduits may be closer to a first side of the body than the mixture conduits and the second conduits. The second conduits may closer to another side of the body than the first conduits and the mixture conduits. The internal volume may receive liquid streams from an injector. The first conduits and the second conduits may receive gas streams from outside the body. The body may thermally modify the gas streams and entrain the gas streams into the liquid streams in the internal volume. The mixture conduits may be positioned to direct the gas streams entrained into the liquid streams out of the body in directions directed toward the second side of the body and away from the first side of the body.

Abstract: A fuel and gas mixing structure for an engine is provided. This mixing structure includes a body configured to be positioned between a fuel injector and a cylinder of an engine. The body defines an interior volume that is configured to receive gas (e.g., air) from outside the body and to receive one or more streams of fuel from the fuel injector in the interior volume. The body also includes one or more upper channels and one or more lower channels that are configured to provide a substantially similar amount of flow relative to each other to the interior volume The body also defines one or more mixture conduits configured to conduct plumes of the fuel and gas, while mixing, from the interior volume to one or more exit ports and therethrough to the cylinder.

Abstract: Methods and systems are proposed for controlling a temperature of exhaust gases generated by the engine by operating an E-Turbo of the vehicle. In one embodiment, a method is provided, comprising increasing a power generated by an electric machine mechanically coupled with an exhaust turbine of an E-Turbo of a vehicle or adjusting an engine power based on a speed of the exhaust turbine and an air-fuel ratio (AFR) of an engine of the vehicle of the engine responsive to the speed of the exhaust turbine increasing above a threshold turbine speed. By increasing or decreasing the power generated by the electric machine and/or adjusting the engine power, the temperature of the exhaust gas may be maintained within a threshold temperature range where an efficiency of an aftertreatment system may be maximized, thereby reducing an emissions of the vehicle.

Abstract: Various methods and systems are provided for generating exhaust energy and converting exhaust energy to electrical energy while an engine is not running. In one example, a system for an engine comprises: a first turbocharger including a first compressor driven by a first turbine, the first turbine disposed in an exhaust of the engine; a fuel burner fluidly coupled to the exhaust upstream of the first turbine; a generator coupled to one of the first turbine or an auxiliary, second turbine fluidly coupled to the exhaust downstream of the fuel burner; and one or more bypass valves configured to adjust a flow of air that bypasses the engine and is delivered to the fuel burner.

Abstract: Various methods and systems are provided for generating exhaust energy and converting exhaust energy to electrical energy while an engine is not running. In one example, a system for an engine comprises: a first turbocharger including a first compressor driven by a first turbine, the first turbine disposed in an exhaust of the engine; a fuel burner fluidly coupled to the exhaust upstream of the first turbine; a generator coupled to one of the first turbine or an auxiliary, second turbine fluidly coupled to the exhaust downstream of the fuel burner; and one or more bypass valves configured to adjust a flow of air that bypasses the engine and is delivered to the fuel burner.

Abstract: A system for controlling a hybrid propulsion system includes a computer programmed to obtain altitude and terrain information associated with a predetermined route for the hybrid propulsion system comprising a first energy source and a second energy source. The computer is also programmed to obtain current and forecast ambient weather information associated with the predetermined route of the hybrid propulsion system, determine a power requirement and a torque requirement of the hybrid propulsion system associated with the altitude and the terrain along the predetermined route of the hybrid propulsion system, generate a trip plan to optimize at least one of a plurality of performance parameters of the hybrid propulsion system as the hybrid propulsion system travels along the predetermined route, and preferentially select the first energy source and/or the second energy source based on the trip plan.

Abstract: A rotating detonation combustion (RDC) system is provided. The RDC includes a first outer wall and a second outer wall each extended around a centerline axis, and a detonation chamber formed radially inward of the second outer wall. A fuel passage extended between the first outer wall and the second outer wall, the fuel passage including a first inlet opening proximate to the aft end through which a flow of fuel is received into the fuel passage. The flow of fuel is provided through the fuel passage from the aft end to the forward end of the RDC system and to the detonation chamber.

Abstract: A combustion system includes an annular tube disposed between an inner wall and an outer wall, the annular tube extending from an inlet end to an outlet end; at least one fluid inlet disposed in the annular tube proximate the inlet end, the fluid inlet providing a conduit through which fluid flows into the annular tube; at least one outlet disposed in the annular tube proximate the outlet end; at least one primary fuel injector, the primary fuel injector dispersing fuel into a fluid stream entering the annular tube via the fluid inlet; and at least one secondary fuel injector, the secondary fuel injector disposed in the annular tube.

Abstract: A system for controlling a hybrid propulsion system includes a computer programmed to obtain altitude and terrain information associated with a predetermined route for the hybrid propulsion system comprising a first energy source and a second energy source. The computer is also programmed to obtain current and forecast ambient weather information associated with the predetermined route of the hybrid propulsion system, determine a power requirement and a torque requirement of the hybrid propulsion system associated with the altitude and the terrain along the predetermined route of the hybrid propulsion system, generate a trip plan to optimize at least one of a plurality of performance parameters of the hybrid propulsion system as the hybrid propulsion system travels along the predetermined route, and preferentially select the first energy source and/or the second energy source based on the trip plan.

Abstract: A control system includes a communication device onboard a vehicle system approaching or entering an airflow restricted area along a route and one or more processors. The communication device configured to receive status messages that contain data parameters representative of ambient conditions within the airflow restricted area. The processors are configured to monitor the ambient conditions and determine different power output upper limits that a trail propulsion vehicle of the vehicle system can generate within the airflow restricted area based on the ambient conditions and different power outputs generated by a lead propulsion vehicle of the vehicle system. The processors further configured to communicate instructions to control the lead propulsion vehicle within the airflow restricted area to generate the power output of the different power outputs that results in the greatest total available power output of the vehicle system as the vehicle system travels within the airflow restricted area.

Abstract: A computer-implemented method for multi-mode operation of a combustion system, a combustion system, and a heat engine are provided. The method includes initializing combustion of a fuel/oxidizer mixture, determining whether conditions at the combustion system meet or exceed a first threshold operating parameter, transitioning to detonation combustion of the fuel/oxidizer mixture if conditions at the combustion system meet or exceed the first threshold operating parameter, and maintaining or increasing fuel flow through a deflagrative fuel circuit if conditions at the combustion system do not meet or exceed the first threshold operating parameter.