Turbocharger system for internal combustion engines

An internal combustion engine/turbocharger system in which the internal combustion engine is provided with at least one variable-volume combustion chamber and has an engine displacement determined by the sum of the differences between the smallest and the largest volume of the combustion chambers of the internal combustion engine, and in which the turbocharger system assigned to the internal combustion engine has at least one turbine, which is arranged in the exhaust path of the internal combustion engine and has a flow duct which opens via a region in the form of an annular nozzle onto a turbine rotor, into the inlet cross section of which a shut-off device can be introduced for the braking mode, by means of which shut-off device, as a fixed restrictor, the cross section of flow at the transition to the turbine rotor can be defined, characterized in that the exhaust path to the turbine is additionally provided with a blow-off valve, the opening cross section of which can be controlled, and in that, based on braking operation at the maximum braking power of the internal combustion engine, there is the following relationship between

• a cross section of flow AT exposed in the exhaust path to the turbine by the shut-off device and the blow-off valve at maximum braking power,
• an inlet diameter DT of the turbine rotor and
• a displacement VH of the internal combustion engine:
• TBF = A T × D T V H
• where TBF, which denotes the turbo-braking factor, is less than 0.005 (5%).