Turbomachine Rotor Cooling

摘要

A rotor (12) of a turbomachine includes a rotor drum (64) located at a central axis (14) and a plurality of buckets (16) secured to the rotor drum (64). A rotor shell (38) extends between axially adjacent buckets of the plurality of buckets (16) and is secured to and supported by the plurality of buckets (16) defining a cooling passage (50) between the rotor drum (64) and the rotor shell (38). A low pressure sink (52) is located at an upstream end of the rotor (12) receptive of a coolant flow through the cooling passage (50). A method of cooling a rotor (12) of a steam turbine (10) includes locating a rotor shell (38) radially outboard of a rotor drum (64) defining a cooling passage (50) therebetween. A flow of steam (60) is urged from a downstream portion of the steam turbine (10) through the cooling passage (50) toward a low pressure sink (52) located at an upstream end of the steam turbine (10) thereby cooling the rotor (12).