An engine system includes an engine having a combustion chamber, an intake gas passage through which air to be supplied to the combustion chamber flows, an exhaust gas passage through which exhaust gas generated from the combustion chamber flows, a reformer configured to reform the fuel to generate a reformed gas containing hydrogen, a gas supply passage through which air to be supplied to the reformer flows, a bypass passage connected to the gas supply passage and the exhaust gas passage so as to bypass the reformer and through which the fuel having passed through the reformer is circulated to an upstream of the reformer, and a switching valve switched between a normal position that does not allow the fuel having passed through the reformer to flow to the bypass passage and a circulating position that allows the fuel having passed through the reformer to flow to the bypass passage.

The present disclosure relates to a combustion process for an internal combustion engine, in which a fuel mixture composed of a dimethyl ether-containing first fuel and a methane-containing second fuel is combusted, wherein the premixed fuel mixture or the fuels independently are fed directly to at least one combustion chamber of the internal combustion engine and/or indirectly via at least one intake pipe of the internal combustion engine upstream of the at least one combustion chamber, wherein the fuel mixture present in the respective combustion chamber is combusted by self-ignition with addition of combustion air on the intake pipe side.

An engine operable in a premixed combustion system and a diffusion combustion system. The engine includes a main fuel injection valve, a pilot fuel injection valve, a liquid fuel tank, a main fuel supply path, a pilot fuel supply path, a pilot fuel filter, a pilot fuel high-pressure pump, a pilot fuel tank, and a pilot fuel supply pump. The pilot fuel tank stores pilot fuel sent from the pilot fuel high-pressure pump and not injected by the pilot fuel injection valve. This pilot fuel is sent to an automatic backwash filter and a pilot fuel filter while not passing through the liquid fuel tank.

Operating an engine includes injecting a liquid alcohol fuel such as methanol into a stream of compressed intake air at an upstream injection location, and injecting the liquid fuel at a plurality of downstream injection locations into a plurality of streams of the compressed intake air from an intake manifold to combustion cylinders in the engine. A fueling control unit apportions a total injected quantity of the liquid fuel between the upstream injection location and the plurality of downstream injection locations based on a temperature parameter of the compressed intake air. The compressed intake air is combusted with the liquid fuel and a compression ignition pilot fuel in the plurality of combustion cylinders.

A method provides for operating an engine configured to use a plurality of differing fuels. The method includes determining a fuel combustion ratio of the plurality of differing fuels associated with at least one engine cylinder of the engine based at least in part on one or more of a plurality of characteristic profiles. This maintains one or more of a plurality of actual values associated with usage of the plurality of differing fuels relative to defined corresponding threshold values. The fuel combustion ratio includes a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder. A fuel delivery system delivers the plurality of differing fuels to the at least one engine cylinder based on the fuel combustion ratio.

System for adapting an internal combustion engine to be powered by gaseous fuel in gas phase and by gaseous fuel, an internal combustion engine arrangement comprising the system and a method for adapting an internal combustion liquid fuel engine to be powered by gaseous fuel in gas phase and gaseous fuel in liquid phase.

Various methods and systems are provided for maintaining combustion stability in a multi-fuel engine. In one example, a system comprises a first fuel system to deliver liquid fuel to at least one cylinder of an engine, a second fuel system to deliver gaseous fuel to the at least one cylinder, and a controller. The controller is configured to supply the gaseous fuel to the at least one cylinder, inject the liquid fuel to the at least one cylinder thereby to ignite the liquid fuel and the gaseous fuel in the at least one cylinder via compression-ignition, and adjust an amount of the gaseous fuel relative to an amount 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.

An engine operable in a premixed combustion system and a diffusion combustion system. The engine includes a main fuel injection valve, a pilot fuel injection valve, a liquid fuel tank, a main fuel supply path, a pilot fuel supply path, a pilot fuel filter, a pilot fuel high-pressure pump, a pilot fuel tank, and a pilot fuel supply pump. The pilot fuel tank stores pilot fuel sent from the pilot fuel high-pressure pump and not injected by the pilot fuel injection valve. This pilot fuel is sent to an automatic backwash filter and a pilot fuel filter while not passing through the liquid fuel tank.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.