Gas turbine compressor spool with structural and thermal upgrades

Abstract

An improved spool for a compressor of a gas turbine engine comprising spacer disks disposed between adjacent rotor disks, and a plurality of hollow tie rods that extend through the rotor disks and the spacer disks. The tie rods are tensionable to provide axial preload between the disks, and also conduct active air for thermally conditioning spool components. The spacer disks have an outer portion with a catenary shape that extends between the peripheral rims of the adjacent rotor disks. Sealing teeth located on the outer portion are preferably radially aligned with a web portion that extends radially inward from a center region on the outer portion. Each tie rod has at least one aperture through its wall for transmitting active air. In one embodiment, active air is injected through apertures in the forward stub shaft of the spool and is urged into at least one space between a rotor disk and a spacer disk, then into, along, and out of the hollow tie rods. In another embodiment active air is injected into open forward ends of the tie rods and subsequently dispersed through apertures in the tie rods. The last stage of the compressor includes a pair of mating forward and aft rotor disks with a cavity formed between the disks. A portion of the active air discharged from the tie rods is circulated in the cavity and into the hollow blades which are integral with the rotor disks. A compressor discharge pressure seal extends axially to the last stage aft rotor disk. The seal has teeth which are oriented generally axially, and preferably have a fishmouth configuration.