Abstract: A fuel injector feeds fuel to a combustion chamber of a cylinder of a dual-fuel engine and includes: a main body having a needle guide; a nozzle needle guidable in the needle guide; a needle fuel chamber defined by the main body, coupleable to the combustion chamber, wherein the orifices are open in a first position of the nozzle needle and closed in a second position of the nozzle needle; a first line arranged in the main body, and being coupled to the needle fuel chamber, via the first line a fuel being introduceable into the needle fuel chamber. In the main body a second line is coupleable to the needle guide and to a control chamber of a control valve of the fuel injector, wherein via the second line a fuel is feedable to the needle guide as barrier fluid and to the control chamber as working fluid.

Abstract: A dual-fuel internal combustion engine includes: cylinders for combusting a first liquid fuel having a first ignitability in a first operating mode, and a second liquid fuel having a second lesser ignitability, in a second operating mode; a main injection system including a main injector for each cylinder, for feeding the first liquid fuel to the respective cylinders in the first operating mode and for feeding the second liquid fuel to the respective cylinders in the second operating mode; and a pilot injection system including a pilot injector for each cylinder, via which the first liquid fuel can is feedable to the respective cylinders in the second operating mode for igniting the second liquid fuel. The main and pilot injection systems are coupled such that in the second operating mode the first liquid fuel, is feedable to the respective main injector as a working fluid and/or a barrier fluid.

Abstract: A fuel injector feeds fuel to a combustion chamber of a cylinder of a dual-fuel engine and includes: a main body having a needle guide; a nozzle needle guidable in the needle guide; a needle fuel chamber defined by the main body, coupleable to the combustion chamber, wherein the orifices are open in a first position of the nozzle needle and closed in a second position of the nozzle needle; a first line arranged in the main body, and being coupled to the needle fuel chamber, via the first line a fuel being introduceable into the needle fuel chamber. In the main body a second line is coupleable to the needle guide and to a control chamber of a control valve of the fuel injector, wherein via the second line a fuel is feedable to the needle guide as barrier fluid and to the control chamber as working fluid.

Abstract: A dual-fuel internal combustion engine includes: cylinders for combusting a first liquid fuel having a first ignitability in a first operating mode, and a second liquid fuel having a second lesser ignitability, in a second operating mode; a main injection system including a main injector for each cylinder, for feeding the first liquid fuel to the respective cylinders in the first operating mode and for feeding the second liquid fuel to the respective cylinders in the second operating mode; and a pilot injection system including a pilot injector for each cylinder, via which the first liquid fuel can is feedable to the respective cylinders in the second operating mode for igniting the second liquid fuel. The main and pilot injection systems are coupled such that in the second operating mode the first liquid fuel, is feedable to the respective main injector as a working fluid and/or a barrier fluid.