vinkelrotorer

Vinkelrotorer, literally “angle rotors” in Swedish, refer to a class of rotor designs in which the blades or vanes are mounted at a fixed angle relative to the plane perpendicular to the rotor axis. This angular offset causes the flow entering or leaving the rotor to acquire an axial component in addition to the tangential component produced by rotation, thereby altering the velocity triangle of the working fluid.

The operating principle of vinkelrotorer is to convert mechanical energy into a modified flow field by directing a portion of the fluid velocity along the axis. The blade pitch angle determines the balance between axial and tangential components, which in turn influences pressure rise, thrust, and overall efficiency. In some configurations, the angle can be fixed, while in others the blades are designed for adjustable pitch to suit different operating conditions.

Construction and design characteristics commonly include blade profiles optimized for the intended fluid and speed range, a hub or mounting arrangement that maintains a precise angular alignment, and, in adjustable variants, a mechanism to vary the pitch during operation. Vinkelrotorer can be found in various turbomachinery contexts, including centrifugal and axial machines, where the angled blades help tailor flow behavior, pressure rise, and flow separation in particular regimes.

Advantages of angled rotor designs include potential improvements in flow control and efficiency for specific operating points, as well as the ability to tailor thrust or pressure characteristics. Limitations involve increased mechanical complexity, tighter tolerances, higher stresses on blades at angle, and manufacturing cost. The term is primarily used in Swedish-language engineering literature, with English literature often describing similar concepts under related terms such as angled, skewed, or pitched rotors.