Abstract: A method for operating a spark ignited engine, including forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder in an intake stroke, and compressing the combustible mixture with a piston in a compression stroke thereby introducing a part of the combustible mixture into a pre-chamber. During the intake and/or the compression stroke, a second fuel is introduced into the pre-chamber at an introduction-time before start of combustion, and the second fuel is of the same or different chemical composition and/or concentration with respect to the first fuel, and a spark ignites in the prechamber. An amount of second fuel and/or the chemical composition of second fuel introduced to the pre-chamber and/or spark timing of the pre-chamber and/or an in-cylinder charge temperature is chosen such that a desired duration of combustion can be achieved.

Abstract: A dual-fuel internal combustion engine with a device for regulating the internal combustion engine, with at least two piston-cylinders, a fuel injector assigned to the piston-cylinder units for a liquid fuel, which has an injector needle. Each piston-cylinder unit has a gas supply device for fuel, wherein the regulating device controls the fuel injector and the at least one gas supply device individually for metering of the quantity of the liquid or gaseous fuel supplied to each piston-cylinder unit. At least one needle sensor is connected to the regulating device and assigned to the respective piston-cylinder unit, which detects a characteristic signal of the needle position in the ballistic range, so that the fuel injector can be operated with individual controllability for each of the at least two piston-cylinder units for the regulation of the supplied fuel quantity in the ballistic range.

Abstract: A method includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into a cylinder, compressing the combustible mixture with a piston in a compression stroke, introducing a second fuel into a prechamber at an introduction-time before start of combustion thus creating a prechamber charge, in which the second fuel being of the same or different chemical composition and/or concentration with respect to the first fuel, and spark igniting the prechamber charge. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored. If emissions and/or mechanical stress are above respective predetermined thresholds, individually for the at least one cylinder, the chemical composition and/or the amount of second fuel introduced into the prechamber, and/or temperature of the cylinder charge and/or spark timing, are changed.

Abstract: A dual-fuel internal combustion engine with a device for regulating the internal combustion engine, with at least two piston-cylinders, a fuel injector assigned to the piston-cylinder units for a liquid fuel, which has an injector needle. Each piston-cylinder unit has a gas supply device for fuel, wherein the regulating device controls the fuel injector and the at least one gas supply device individually for metering of the quantity of the liquid or gaseous fuel supplied to each piston-cylinder unit. At least one needle sensor is connected to the regulating device and assigned to the respective piston-cylinder unit, which detects a characteristic signal of the needle position in the ballistic range, so that the fuel injector can be operated with individual controllability for each of the at least two piston-cylinder units for the regulation of the supplied fuel quantity in the ballistic range.

Abstract: A method for operating a compression ignition engine includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder, compressing the combustible mixture with the piston in a compression stroke, injecting a second fuel to the combustible mixture at an injection-time of the second fuel during the compression stroke but before start of combustion, and continuing the compression stroke until combustion starts at those locations in the at least one cylinder where concentration of the second fuel is highest and/or the temperature of the mixture is the highest. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored, and if emissions and/or mechanical stress are above respective predetermined thresholds, individually for the cylinder, the amount and/or the timing of the second fuel injected, and/or temperature of the cylinder charge is changed.

Abstract: A method for operating a spark ignited engine, including forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder in an intake stroke, and compressing the combustible mixture with a piston in a compression stroke thereby introducing a part of the combustible mixture into a pre-chamber. During the intake and/or the compression stroke, a second fuel is introduced into the pre-chamber at an introduction-time before start of combustion, and the second fuel is of the same or different chemical composition and/or concentration with respect to the first fuel, and a spark ignites in the prechamber. An amount of second fuel and/or the chemical composition of second fuel introduced to the pre-chamber and/or spark timing of the pre-chamber and/or an in-cylinder charge temperature is chosen such that a desired duration of combustion can be achieved.

Abstract: A method includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into a cylinder, compressing the combustible mixture with a piston in a compression stroke, introducing a second fuel into a prechamber at an introduction-time before start of combustion thus creating a prechamber charge, in which the second fuel being of the same or different chemical composition and/or concentration with respect to the first fuel, and spark igniting the prechamber charge. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored. If emissions and/or mechanical stress are above respective predetermined thresholds, individually for the at least one cylinder, the chemical composition and/or the amount of second fuel introduced into the prechamber, and/or temperature of the cylinder charge and/or spark timing , are changed.

Abstract: A method of operating a compression ignition engine uses an engine having a cylinder and a piston moveable in the cylinder. The method includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder, and compressing the combustible mixture with the piston in a compression stroke. During the compression stroke but before start of combustion, a second fuel is added to the combustible mixture, thus creating a cylinder charge, the second fuel being easier to autoignite than the first fuel. The compression stroke is continued until combustion starts at those locations in the cylinder where concentration of the second fuel and/or temperature of the mixture is highest. A temperature of the cylinder charge and/or the amount of second fuel added to the combustible mixture is chosen such that a desired duration of combustion can be achieved.

Abstract: A method for operating a compression ignition engine includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder, compressing the combustible mixture with the piston in a compression stroke, injecting a second fuel to the combustible mixture at an injection-time of the second fuel during the compression stroke but before start of combustion, and continuing the compression stroke until combustion starts at those locations in the at least one cylinder where concentration of the second fuel is highest and/or the temperature of the mixture is the highest. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored, and if emissions and/or mechanical stress are above respective predetermined thresholds, individually for the cylinder, the amount and/or the timing of the second fuel injected, and/or temperature of the cylinder charge is changed.