Shroud arrestor for bladed powerplant rotor

An assembly for a powerplant, comprising:

• a radial flow rotor configured to rotate about an axis, the radial flow rotor including a rotor base and a plurality of rotor blades arranged circumferentially around and connected to the rotor base;
• a rotor shroud circumscribing the radial flow rotor, the rotor shroud disposed adjacent tips of the plurality of rotor blades;
• and
• a shroud arrestor structurally disengaged from the rotor shroud, the shroud arrestor including an arrestor body and an arrestor mount, the arrestor body circumscribing the rotor shroud and projecting longitudinally out from the arrestor mount to a distal end of the shroud arrestor, and the arrestor body having a cone shaped geometry;
• the rotor shroud including a shroud wall and a shroud mount, the shroud wall disposed adjacent the tips of the plurality of rotor blades, an annular groove formed by and extending between the shroud wall and the shroud mount, and the arrestor body projecting longitudinally into the annular groove to the distal end of the shroud arrestor.

An assembly for a powerplant, comprising:

• a radial flow rotor configured to rotate about an axis, the radial flow rotor including a rotor base and a plurality of rotor blades arranged circumferentially around and connected to the rotor base;
• a rotor shroud circumscribing the radial flow rotor, the rotor shroud disposed adjacent tips of the plurality of rotor blades;
• and
• a shroud arrestor including an arrestor body and an arrestor mount, the arrestor body cantilevered from the arrestor mount and circumscribing the rotor shroud, the arrestor body projecting longitudinally out from the arrestor mount to a distal end of the shroud arrestor, and the arrestor body configured with an elliptical segment sectional profile between the arrestor mount and the distal end of the shroud arrestor;
• the rotor shroud including a shroud wall and a shroud mount, the shroud wall disposed adjacent the tips of the plurality of rotor blades, an annular groove formed by and extending between the shroud wall and the shroud mount, and the arrestor body projecting longitudinally into the annular groove to the distal end of the shroud arrestor.