Rotor for large hydroelectric machine - has non-circular rim for compensating deformation at high speed by evolving circular shape

摘要

The rotor (1) has a control hub (2) and radial rotor blades (3), with a rim (4) joining their outer ends. The rim (4) has a non-circular configuration when the rotor is at rest, to allow for the deformation caused during high speed rotation, such that it exhibits a circular configuration at the required rotation rate with a given rotor temp. distribution. Pref. the rotor blades are integral with the rim and the hub and are prestressed in the radial direction when the rotor is at rest. The deviation of the rim from a circular configuration may be obtained by forcing the rotor blades between the hub and a slightly undersized circular rim, or it may be formed initially in the required shape.