US 6,267,553 B1 · 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.

Claims41

Dependent claims

In a gas turbine including a compressor for producing a main air stream, the compressor having a stator and a spool comprised of multiple axial stages extending between a first stage at a forward end of the compressor and a last stage at an aft end of the compressor, each stage including a rotor disk having a peripheral rim and multiple blades attached to the rim, the first stage rotor disk having a front stub shaft extending in a forward direction, the last stage rotor disk having a rear stub shaft extending in an aft direction, the improvement comprising:

(a) a spacer disk disposed between adjacent rotor disks, the spacer disk having an outer portion and a web portion, the outer portion extending generally axially between the peripheral rims of the adjacent rotor disks, the outer portion having a forward end, an aft end and a center region between the forward end and the aft end, the web portion extending radially inward from the center region;
and
(b) a plurality of tie rods, each tie rod having a hollow interior for conducting air, the tie rods extending through the rotor disks and the spacer disks, the tie rods being tensionable to provide axial preload between the disks.

In a gas turbine including a compressor for producing a main air stream, the compressor having a stator and a spool comprised of multiple stages extending between a first stage at a forward end of the compressor and a last stage at an aft end of the compressor, each stage including a rotor disk having a peripheral rim and multiple blades attached to the rim, the first stage rotor disk having a front stub shaft extending forward of the rotor disk, the last stage rotor disk having a rear stub shaft extending in an aft direction, the improvement comprising:

(a) a spacer disk disposed between adjacent rotor disks, the spacer disk having an outer portion and a web portion, the outer portion having a catenary shape in cross-section and extending generally axially between the peripheral rims of the adjacent rotor disks, the outer portion having a forward end, an aft end and a center region between the forward end and the aft end, the peripheral rim of each rotor disk having a lip which receives one of the ends of the outer portion, the web portion extending radially inward from the center region of the outer portion, the outer portion having at least one seal tooth extending generally radially outward from the center region to seal against a portion of the stator;
(b) the last stage including a pair of mating forward and aft rotor disks with a cavity formed between the disks, the blades on the last stage include mating forward and aft portions, the forward portion being integral with the forward rotor disk and the aft portion being integral with the aft rotor disk, the blades having an internal cavity in fluid communication with the cavity between the forward and aft rotor disks;
(c) a baffle plate in the cavity between the forward and aft rotor disks, the baffle plate generally bisecting the cavity into a forward portion and an aft portion, the baffle plate having an aft side with radial vanes on the aft side,
(d) a plurality of tie rods, each tie rod having a hollow interior for conducting air and a plurality of apertures, at least one of the apertures providing fluid communication between the interior of the tie rod and the cavity between the forward and aft last stage rotor disks, at least one other aperture providing fluid communication between the interior of the tie rod and a space between a rotor disk and a spacer disk, the tie rods extending through the rotor disks and the spacer disks, the tie rods being tensionable to provide axial preload between the disks;
(e) a plurality of tubular elements on each tie rod to establish axial spacing between the disks and to react tie rod axial preload forces, each tubular element being disposed between adjacent spacer and rotor disks, the tie rod being disposed inside of the tubular elements, at least one of the tubular elements having at least one aperture which aligns with at least one aperture in the tie rod;
and
(f) a compressor discharge pressure seal extending axially forward from a portion of the stator to the last stage aft rotor disk, the seal having teeth oriented generally axially.

4 more elements

(a) a spacer disk disposed between adjacent rotor disks, the spacer disk having an outer portion and a web portion, the outer portion having a catenary shape in cross-section and extending generally axially between the peripheral rims of the adjacent rotor disks, the outer portion having a forward end, an aft end and a center region between the forward end and the aft end, the web portion extending radially inward from the center region;
(b) the last stage including a pair of mating forward and aft rotor disks with a cavity formed therebetween,
(c) a plurality of tie rods, each tie rod having a hollow interior for conducting air and a plurality of apertures, at least one of the apertures providing fluid communication between the interior of the tie rod and the cavity between the forward and aft last stage rotor disks, at least one other aperture providing fluid communication between the interior of the tie rod and a space between a rotor disk and a spacer disk, the tie rods extending through the rotor disks and the spacer disks, the tie rods being tensionable to provide axial preload between the disks;
(d) a compressor discharge pressure seal extending axially forward from a portion of the stator to the last stage aft rotor disk, the seal having teeth oriented generally axially;
(e) system for extracting a portion of the main air stream from a stage before the last stage;
(f) mechanism for selectively routing at least part of the extracted portion of air through a heat exchanger or a bypass of the heat exchanger;
(g) system for injecting at least part of the extracted portion of air from the heat exchanger or from the bypass into the spool at a location in front of the first stage as active air for use in thermal conditioning spool components;
(h) mechanism for passing a portion of active air injected in front of the first stage into the tie rods, through the interior of the tie rods, and out through at least one aperture in the tie rods, one of the apertures through which air flows out directing air into the cavity between the last stage rotor disks;
and
(i) mechanism for passing the air in the cavity between the last stage rotor disks outward along the last stage forward rotor disk, into the last stage blades, and back inward with forced vortex flow along the last stage aft disk.

7 more elements

Dependencies are inferred from the claim text.

Gas turbine compressor spool with structural and thermal upgrades

Life of this patent

Gas turbine compressor spool with structural and thermal upgrades

Life of this patent

Abstract

Claims41