摘要 |
A turbine rotor comprising radially extending blades having inner and outer ends and an axially symmetrical annular shroud having upstream and downstream ends affixed to the blades adjacent the outer ends thereof and rotating with the blades. The annular shroud increases in diameter from its upstream end to its downstream end such that a passage formed thereby widens from its upstream intake opening towards it downstream outlet opening, with the annular shroud in radial section having a profile adapted to produce a lift force under onflow conditions and being oriented such that its suction side forms the interior surface of the annular shroud facing the passage and that its angle of attack relative to a direction extending parallel to the central axis of the annular passage is smaller than the critical (stalling) angle of the profile. A further annular shroud may be fixed to the inner ends of the blades. |