Turbine wheel with composite bladed ring

Abstract

A turbine wheel for use in a gas turbine engine having a bladed ring attached to a rotor disk. The bladed ring includes features to fit within slots of the rotor disk to couple the bladed ring to the rotor disk.

What is claimed is: 
     
         1 . A turbine wheel for a gas turbine engine, the turbine wheel comprising
 a metallic disk formed to include a slot that extends through the disk in an axial direction from a forward side to an aft side of the disk and inwardly in a radial direction from an outer radius of the disk toward a central axis, and   a composite-bladed ring including a ring positioned to surround the outer radius of the disk, a key extending radially inward of the ring and positioned to engage the slot to maintain circumferential alignment of the ring with the disk during rotation of the metallic disk, and a composite blade coupled to the ring and extending radially outward from the ring.   
     
     
         2 . The turbine wheel of  claim 1 , wherein the ring is unitary and the key is positioned to slide in a radial direction within the slot such that the disk may expand relative to the ring. 
     
     
         3 . The turbine wheel of  claim 2 , wherein the ring is formed to include an outer radius and a thickness such that a gap is positioned between the ring and the disk to allow radial expansion of the disk relative to the ring. 
     
     
         4 . The turbine wheel of  claim 2 , wherein the key has a generally rectangular shape when viewed along the central axis. 
     
     
         5 . The turbine wheel of  claim 2 , wherein the ring resists centrifugal loads placed on the ring independent of the disk during rotation of the disk and composite-bladed ring about the central axis. 
     
     
         6 . The turbine wheel of  claim 5 , wherein the centrifugal loads are carried as hoop stress in the ring. 
     
     
         7 . The turbine wheel of  claim 1 , wherein the ring, the key, and the composite blade are formed as a unitary structure. 
     
     
         8 . The turbine wheel of  claim 1 , further comprising at least one compliant pad having a compliance greater than the metallic disk and the composite bladed ring, the at least one compliant pad arranged in the slot between the metallic disk and the composite bladed ring so that the compliant pad is configured to distribute contact loads between the metallic disk and the composite-bladed ring. 
     
     
         9 . The turbine wheel of  claim 1 , wherein the ring is formed to include a dovetail slot that extends through the ring in an axial direction from a forward side to an aft side of the ring and inwardly in a radial direction from an outer radius of the ring toward the central axis, and wherein the composite blade is formed to include an airfoil that extends outwardly in a radial direction from the outer radius of the ring and a root that extends into the dovetail slot of the ring to retain the blade to the ring. 
     
     
         10 . The turbine wheel of  claim 9 , wherein the composite blade is further formed to include a platform positioned between the airfoil and root. 
     
     
         11 . A turbine wheel for a gas turbine engine, the turbine wheel comprising
 a disk formed to include a dovetail slot that extends through the disk in an axial direction from a forward side to an aft side of the disk and inwardly in a radial direction from an outer radius of the disk toward a central axis, and   a composite-bladed ring including a ring positioned to surround the outer radius of the disk, a root extending radially inward of the ring and positioned to engage the dovetail slot to maintain circumferential alignment of the ring with the disk and resist centrifugal forces applied to the composite-bladed ring, and a composite blade coupled to the ring and extending radially outward from the ring.   
     
     
         12 . The turbine wheel of  claim 11 , wherein the ring is formed to include an outer radius and a thickness; and the outer radius and thickness of the ring are sized such that a gap is positioned between the ring and the disk to allow radial expansion of the disk relative to the ring. 
     
     
         13 . The turbine wheel of  claim 11 , further comprising at least one compliant pad having a compliance greater than the metallic disk and the composite bladed ring, the at least one compliant pad arranged in the slot between the metallic disk and the composite bladed ring so that the compliant pad is configured to distribute contact loads between the metallic disk and the composite-bladed ring 
     
     
         14 . The turbine wheel of  claim 11 , wherein the ring includes at least two ring sections, each ring section positioned to surround a portion of the outer radius of the disk and cooperate with the other ring section to form the ring. 
     
     
         15 . The turbine wheel of  claim 14 , wherein each ring section includes at least one root extending radially inward from the ring section and positioned to engage the disk to retain the ring section to the disk. 
     
     
         16 . The turbine wheel of  claim 11 , wherein the ring is formed to include a dovetail slot that extends through the ring in an axial direction from a forward side to an aft side of the ring and inwardly in a radial direction from an outer radius of the ring toward the central axis, and wherein the composite blade is formed to include an airfoil that extends outwardly in a radial direction from the outer radius of the ring and a root that extends into the dovetail slot of the ring to retain the blade to the ring. 
     
     
         17 . The turbine wheel of  claim 16 , wherein the composite blade is further formed to include a platform positioned between the airfoil and root. 
     
     
         18 . A method of assembling a turbine wheel comprising
 positioning a composite-bladed ring relative to a disk, the composite-bladed ring including a ring positioned to surround an outer radius of the disk, a key extending radially inward of the ring, and a composite blade coupled to the ring and extending radially outward from the ring, and   engaging the key with a slot formed in the disk to maintain circumferential alignment of the ring with the disk during rotation of the composite-bladed ring and disk about a central axis.   
     
     
         19 . The method of  claim 18 , wherein the blades are integral with the ring to form a unitary structure. 
     
     
         20 . A method of assembling a turbine wheel comprising
 positioning a ring of ceramic containing material to surround an outer radius of a disk, the disk formed to include a dovetail slot that extends through the disk in an axial direction from a forward side to an aft side of the disk and inwardly in a radial direction from an outer radius of the disk toward a central axis, and the ring being formed to include a root extending radially inward of the ring and positioned to engage the dovetail slot to maintain circumferential alignment of the ring with the disk, and   coupling a composite blade to the ring, the ring being formed to include a dovetail slot that extends through the ring in an axial direction from a forward side to an aft side of the ring and inwardly in a radial direction from an outer radius of the ring toward the central axis, and the blade formed to include an airfoil and a root that extends from the airfoil into the dovetail slot of the ring to couple the blade to the ring.