1. Field of the Invention
The invention pertains to a hydrodynamic retarder with a first blade wheel and with a second blade wheel, concentric to the first, which together form a hydrodynamic circuit and are grouped around a common axis of rotation, wherein each blade wheel consists of a base body and a blading with a plurality of blades permanently attached to the base body.
2. Prior Art
A hydrodynamic retarder with a first blade wheel, acting as a rotor blade wheel, and with a second blade wheel, concentric to the first, acting as a stator blade wheel, is known from EP 1 305 535 B1. These two blade wheels together form a hydrodynamic circuit and are grouped around a common axis of rotation, wherein each blade wheel consists of a base body and a blading with a plurality of blades permanently attached to the base body. Fluid is supplied to the hydrodynamic circuit through a fluid inlet, and fluid is discharged from the hydrodynamic circuit through a fluid outlet.
Retarders of this type suffer from the basic problem that cavitation can occur as a result of the high-speed infeed of fresh fluid into the hydrodynamic circuit. This cavitation can cause damage to the blading of the stator blade wheel, usually in the radially outer area of the blades. For this reason, all of the blades on the stator blade wheel have a bevel in the radially outer area, extending back from the flow edge, i.e., the edge which faces the rotor blade wheel. Nevertheless, this solution merely limits the effects of cavitation; it does nothing to prevent its occurrence.