Cooled turbine blade ring assembly

Claim 1

A hot elastic fluid machine, comprising: a turbine casing, a plurality of rotatable diScs mounted on an axis, a plurality of rotor blades disposed on the periphery of each of said rotatable discs, a plurality of radially directed stationary blades disposed in annular arrays alternating with said rotatable discs, each annular array of stationary blades having an inner and an outer shroud ring, a blade ring circumferentially disposed about the blades, means for supplying said stationary blades with cooling fluid, a plurality of insulated ring segments coaxial with said blade ring disposed radially outwardly of said rotating blades and inwardly of said blade ring, conduit means for supplying pressurized cooling fluid to said ring segments, said ring segments disposed about said rotating blades being expansible in both the radial and the axial direction, said radial direction of expansion of said ring segments being controlled by a biasing means, and a heat shield, said heat shield being disposed in a spaced relationship and radially outwardly of, yet fixedly attached to, said ring segments, said heat shield being cooled by chambers having a passageway extending therethrough, said passageway permitting the flow of cooling fluid through said bias producing means, the radially innermost chamber having holes therein, said holes permitting the pressurized cooling fluid to impinge upon said heat shield, the flow of cooling fluid upon said heat shield preventing localized overcooling and hence preventing localized distortion of said ring segments thereby, said heat shield receiving heat from said ring segments by radiation and convection to permit a uniform temperature across said ring segments and, said heat shield providing a heat barrier between said blade ring and said ring segments.