COMPOSITE CASING FOR ROTATING BLADES

• US 20110052382A1
• Filed: 08/26/2009
• Published: 03/03/2011
• Est. Priority Date: 08/26/2009
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Original Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Inventors: Cheung, Kin-Leung
• Granted Patent: US 8,545,167 B2
• Time in Patent Office: Days
• US Class Current: 415/200
• CPC Class Codes: F04D 27/0292 Stop safety or alarm devices, e.g. stop-and-go control; Disposition of check-valves
• CPC Class Codes: F04D 29/023 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/526 Details of the casing section radially opposing blade tips ducts F04D29/545
• CPC Class Codes: F05D 2300/43 Synthetic polymers, e.g. plastics; Rubber
• CPC Class Codes: F05D 2300/603 Composites; e.g. fibre-reinforced
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A gas turbine engine includes a fan including a plurality of circumferentially spaced rotatable blades, and a fan casing for containing fragments of fan blades in the event of blade release, the fan casing having a shell surrounding the blades and circumscribing a containment zone of the fan. The shell is made of a fiber reinforced polymer composite material which includes nanoparticles.

Claims

1. A gas turbine engine comprising:

a fan including a plurality of circumferentially spaced rotatable blades; and

a casing for containing fragments of the blades in the event of blade release, the casing including a shell surrounding the blades and circumscribing a containment zone of the fan, the shell being made of a fiber reinforced polymer composite material including nanoparticles.

2. The engine as defined in claim 1, wherein the composite material has a content of the nanoparticles of at least 2 phr.

3. The engine as defined in claim 1, wherein the composite material has a content of the nanoparticles of up to 10 phr.

4. The engine as defined in claim 1, wherein the nanoparticles include one or more selected from the group consisting of clay, clay based reinforcements, particle dispersions, hyper-branched polymers, nano-spheres, elements, and nanolarge pendant groups grafted on the end of a chain of the polymer.

5. The engine as defined in claim 1, wherein the nanoparticles include one or more selected from the group consisting of montmorillonite, magnetic particles, Cobalt iron oxide, ceramic powders, carbon, and carbon nano-tubes.

6. The engine as defined in claim 1, wherein the fiber reinforced polymer composite material includes a polymer resin having reinforcing fibers therein, the polymer resin being selected from the group consisting of epoxy, polyphenylene sulfide (PPS), polyetheretherketone (PEEK) and polyetherketoneketone (PEKK), and the reinforcing fibers being selected from the group consisting of carbon fibers, aromatic polyamide (aramid fibers), ultra high molecular weight polyethylene fibers, poly(diimidazo pyridinylene (dihydroxy) phenylene) fibers, and poly(p-phenylene-2-6-benzobisoxazole) fibers.

7. The engine as defined in claim 1, wherein the shell is a first shell, the casing further comprising a second shell surrounding the first shell, the second shell being made of a fiber reinforced polymer composite material including nanoparticles, the second shell including a higher ratio of continuous fiber to resin content than that of the first shell.

8. A casing for surrounding rotating blades and containing blade fragments thereof in the event of blade release, the casing comprising a shell made of a composite material including a polymer resin, reinforcing fibers and nanoparticles, the fibers forming a first bond with the resin resisting separation up to a first mean impact energy threshold, the nanoparticles forming a second bond with the resin resisting separation up to a second mean impact energy threshold, the first mean impact energy threshold being substantially greater than the second mean impact energy threshold, such that upon impact of blade fragments with the casing, separation of the nanoparticles from the resin absorbs a portion of the impact energy.

9. The casing as defined in claim 8, wherein the composite material has a content of the nanoparticles of up to 10 phr.

10. The casing as defined in claim 8, wherein the nanoparticles include one or more selected from the group consisting of clay, clay based reinforcements, particle dispersions, hyper-branched polymers, nano-spheres, elements, and nanolarge pendant groups grafted on the end of a chain of the polymer.

11. The casing as defined in claim 8, wherein the nanoparticles include one or more selected from the group consisting of montmorillonite, magnetic particles, Cobalt iron oxide, ceramic powders, carbon, and carbon nano-tubes.

12. The casing as defined in claim 8, wherein the polymer resin is selected from the group consisting of epoxy, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and polyetherketoneketone (PEKK), and the fibers are selected from the group consisting of carbon fibers, aromatic polyamide (aramid fibers), ultra high molecular weight polyethylene fibers, poly(diimidazo pyridinylene (dihydroxy) phenylene) fibers, and poly-phenylene-2-6-benzobisoxazole) fibers.

13. The casing as defined in claim 8, wherein the shell is a first shell, the composite material is a first composite material, and the polymer resin, reinforcing fibers and nanoparticles are first polymer resin, reinforcing fibers and nanoparticles, respectively, the casing further comprising a second shell surrounding the first shell, the second shell being made of a second composite material including a second polymer resin, second reinforcing fibers and second nanoparticles, the first composite material being identical or different from the second composite material, a ratio of a fiber to resin content in the second composite material being higher than that of the first composite material.

14. A method of manufacturing a fan casing having improved blade containment capability, the method comprising forming the fan casing from a composite material including a polymer resin, reinforcing fibers and nanoparticles, the nanoparticles having an area of resin interface per volume substantially greater than that of the reinforcing fibers, an average impact energy threshold necessary for causing separation of any one of the nanoparticles from the resin being substantially lower than that for causing separation or breaking of any one of the fibers in the resin, such that during impact of a blade or a blade portion on the casing, the lower impact energy threshold of the nanoparticles causes separation of the nanoparticles from the resin to predominate over separation of the fibers from the resin or breaking of the fibers in the resin, thus limiting a reduction of a structural integrity of the casing caused by the impact, and the greater area of interface per volume of the nanoparticles limits an area of damage caused by the impact.

15. The method as defined in claim 14, wherein forming the fan casing includes adding up to 10 phr of the nanoparticles.

16. The method as defined in claim 14, wherein forming the fan casing includes selecting the nanoparticles from the group consisting of montmorillonite, clay based reinforcements other than montmorillonite, magnetic particles, Cobalt iron oxide, particle dispersions other than magnetic particles and Cobalt iron oxide, hyper-branched polymers, ceramic powders, nano-spheres other than ceramic powders, carbon particles, carbon nano-tubes, elements other than carbon particles and carbon nano-tubes, and nanolarge pendant groups grafted on the end of a chain of the polymer.