Methods and systems are provided for coordinating water usage with spark usage based on the effect on an engine torque ratio. Water is injected based on torque ratio at a current spark timing relative to torque ratio at borderline knock to improve the impact of the water injection on the engine performance. Manifold water injection and direct water injected are coordinated based on intake manifold humidity.

A device for injecting water into an internal combustion having a tank for storage and provision of water, an injector for injecting the water into the internal combustion engine, which injector is connected to the tank, a control unit for controlling the injector 6, and a decontamination unit which has at least one element with a contact surface which, with formation of a surface contact with the water, acts in a decontaminating manner to provide decontaminated water for injection.

A device for injecting water into an internal combustion having a tank for storage and provision of water, an injector for injecting the water into the internal combustion engine, which injector is connected to the tank, a control unit for controlling the injector 6, and a decontamination unit which has at least one element with a contact surface which, with formation of a surface contact with the water, acts in a decontaminating manner to provide decontaminated water for injection.

A method for operating a device for injecting water into an internal combustion engine, the device including a water tank for storing water, a pump for conveying the water, the pump being connected to the water tank via a first line, and the pump being operable in a conveying mode and in a back-suction mode, a drive for driving the pump, at least one water injector, which is configured to inject water into an air-conducting line of the internal combustion engine, the water injector being connected to the pump via a second line, the at least one water injector being opened during the operation of the pump in the back-suction mode, in which the water is conveyed in the direction of the water tank, so that air flows into the second line.

A method for operating a device for injecting water into an internal combustion engine, the device including a water tank for storing water, a pump for conveying the water, the pump being connected to the water tank via a first line, and the pump being operable in a conveying mode and in a back-suction mode, a drive for driving the pump, at least one water injector, which is configured to inject water into an air-conducting line of the internal combustion engine, the water injector being connected to the pump via a second line, the at least one water injector being opened during the operation of the pump in the back-suction mode, in which the water is conveyed in the direction of the water tank, so that air flows into the second line.

A method for controlling an engine system, may include a water injection operation of injecting water into an intake system of an engine through a water injector of a water injection system in a first operating condition of the engine in which water injection is required, a compressed air injection operation of injecting compressed air into the intake system through a purge circuit of the water injection system in a second operating condition of the engine in which compressed air injection is required, and a water injection stop operation of stopping the water injection of the water injection system in a third operating condition of the engine in which water injection stop is required.

A method for controlling an engine system, may include a water injection operation of injecting water into an intake system of an engine through a water injector of a water injection system in a first operating condition of the engine in which water injection is required, a compressed air injection operation of injecting compressed air into the intake system through a purge circuit of the water injection system in a second operating condition of the engine in which compressed air injection is required, and a water injection stop operation of stopping the water injection of the water injection system in a third operating condition of the engine in which water injection stop is required.

An engine/reformer system accepts a first fuel and reforms it into syngas for use as a fuel in an accompanying internal combustion engine. Prior to reforming, the first fuel is pressurized and/or heated to at or near supercritical fluid conditions, such that the resulting syngas leaves the reformer in a supercritical fluid state. Injection of the supercritical syngas into an engine cylinder avoids the autoignition problems that occur when gaseous syngas is used. The first fuel is a fully self-reforming fuel (one that needs no separate water supply for complete conversion to syngas), and can beneficially be a wet fuel, such as ethanol containing water, allowing the system to use intermediate products of an ethanol production process (such as hydrous ethanol and stillage wastewater) as fuel, and reducing the overall cost of fuel production and engine operation.

Methods and systems are provided for implementing fluid injection through a cylinder valve seat. The engine system may include a cylinder valve with a valve head mating with a valve seat when the valve is closed. The valve seat includes an injection orifice blocked by the valve head when the cylinder valve is closed and unblocked when the cylinder valve is opened.

A water injection device of an internal combustion engine, including a water tank for storing water, at least one water injector, a conveying element for conveying water from the water tank into the water injector, and a shut-off element, which is situated in an area between the conveying element and the water injector, and which is configured to maintain a system pressure between the shut-off element and the water injector at a level such that water situated in the area is prevented from evaporating. An internal combustion engine, which includes a water injection device.