초록

Turbine blades are held in long arc groups by a shroud structure, with gaps between segments of the shroud structure. These gaps are Z-shaped, the gaps tending to close due to untwisting of the blades when the blades are subjected to high centrifugal forces.

대표청구항 ▼

A rotor structure for an axial flow elastic fluid utilizing machine comprising: (a) a rotor spindle; (b) an annular row of radially extending blades carried by the rotor spindle; and (c) a non-integral arcuate shroud ring structure, attached to the radially outermost tips of the blades for rigidly c

A rotor structure for an axial flow elastic fluid utilizing machine comprising: (a) a rotor spindle; (b) an annular row of radially extending blades carried by the rotor spindle; and (c) a non-integral arcuate shroud ring structure, attached to the radially outermost tips of the blades for rigidly connecting the blades to each other in long arc groups comprising at least 12 blades, the shroud ring structure being divided into shroud segments with gaps therebetween, one shroud segment for each group, the long arc groups being of substantially equal central angular extend, the number of long arc groups being equal to the blade resonant frequency divided by an integer multiple of the rotor running speed; the blade tips being skewed relative to the direction of rotation of the shroud, the shroud segments having a leading end and a trailing end, at least one pair of adjacent segments having their adjoining ends configured to be flexibly interlocked to each other without connectors at a gap that is completely between blade tips, with the adjoining ends having a “Z”configuration comprising two end sections connected by a section substantially parallel to the direction of rotation of the shroud, the two end sections being transverse to the direction of rotation of the shroud, such that when the machine is in operation, the blades tend to untwist resulting in the gap closing in the middle section of the “Z”configuration.