Method and apparatus for cooling a rotor assembly

A support assembly for a set of rotor winding end turns extending from a rotor core of an electrical machine having a rotatable shaft, the support assembly comprising:

• a first collar including a first wall having an annular first surface facing an axial end of the rotor core, an opposing annular second surface, and an annular third surface defining a first bore extending from the annular first surface to the annular second surface, the first collar further including an annular second wall coupled to the first wall and extending axially therefrom toward the rotor core arranged to radially overlie the rotor winding end turns, the annular second wall having a radially outward facing annular fourth surface, and an opposing annular fifth surface facing the rotor winding end turns;
• a second collar axially disposed between the rotor core and the first collar, including a third wall disposed between the first wall and the rotor winding end turns, the third wall having an annular sixth surface facing the axial end of the rotor core, and an opposing seventh surface, the third wall further including an annular eighth surface defining a second bore, the second collar further including an annular fourth wall coupled to the third wall and extending axially therefrom toward the rotor core and disposed between the rotor winding end turns and the annular second wall;
• and
• a coupling disc including an annular fifth wall facing the axial end of the rotor core, the coupling disc further including an annular sixth wall coupled to the annular fifth wall and extending axially therefrom toward the rotor core and radially underlying the rotor winding end turns, the annular sixth wall circumferentially surrounding and coupled to the rotatable shaft;
• wherein the first collar is coupled along the annular third surface to the annular fifth wall at an outer periphery of the coupling disc, and wherein the second collar is coupled to the coupling disc along the annular eighth surface.