초록

A multiple of circumferential grooves within said arcuate engine casing and an abradable material located radial inboard of the multiple of circumferential grooves.

대표청구항 ▼

1. A buried casing treatment strip comprising: a multiple of circumferential grooves; andan abradable material located radial inboard of said multiple of circumferential grooves. 2. The buried casing treatment strip as recited in claim 1, wherein said abradable material and said multiple of circumfe

1. A buried casing treatment strip comprising: a multiple of circumferential grooves; andan abradable material located radial inboard of said multiple of circumferential grooves. 2. The buried casing treatment strip as recited in claim 1, wherein said abradable material and said multiple of circumferential grooves define a rub strip positionable radially outboard of a multitude of circumferentially spaced apart blades which extend radially outwardly from a disk of a gas turbine engine. 3. The buried casing treatment strip as recited in claim 2, wherein said multitude of circumferentially spaced apart blades are compressor blades. 4. The buried casing treatment strip as recited in claim 2, wherein said multitude of circumferentially spaced apart blades are fan blades. 5. The buried casing treatment strip as recited in claim 1, wherein said abradable material is generally flush with an inner surface of an engine casing when installed therein. 6. An engine section comprising: a rotor disk;a multitude of circumferentially spaced apart blades which extend in a radial direction from said disk to a blade tip;an arcuate engine casing which surrounds said blade tips; anda buried casing treatment strip formed within said arcuate engine casing adjacent said blade tips, said buried casing treatment strip having an abradable material located radial inboard of a multiple of circumferential grooves. 7. The engine section as recited in claim 6, wherein said multitude of circumferentially spaced apart blades are compressor blades. 8. The engine section as recited in claim 6, wherein said multitude of circumferentially spaced apart blades are fan blades. 9. A method of mitigating excessive blade tip clearance in a gas turbine engine comprising: revealing a multiple of circumferential grooves through erosion of an abradable material by a multitude of circumferentially spaced apart blades within a gas turbine engine. 10. The method as recited in claim 9, further comprising: locating the abradable material outboard of the multitude of circumferentially spaced apart blades. 11. The method as recited in claim 9, further comprising: locating the multiple of circumferential grooves outboard of the abradable material. 12. The method as recited in claim 9, wherein revealing the multiple of circumferential grooves occurs at a predetermined threshold relative to a stability margin of the gas turbine engine. 13. The buried casing treatment strip as recited in claim 1, wherein said abradable material covers said multiple of circumferential grooves. 14. The buried casing treatment strip as recited in claim 1, wherein said multiple of circumferential grooves are closed grooves opposite said abradable material. 15. The buried casing treatment strip as recited in claim 1, wherein said abradable material closes said multiple of circumferential grooves. 16. The engine section as recited in claim 6, wherein said abradable material covers said multiple of circumferential grooves. 17. The engine section as recited in claim 6, wherein said multiple of circumferential grooves are closed grooves opposite said abradable material. 18. The method as recited in claim 12, wherein revealing the multiple of circumferential grooves restores a stability margin. 19. The method as recited in claim 9, wherein revealing the multiple of circumferential grooves restores a stability margin. 20. The method as recited in claim 9, further comprising covering the multiple of circumferential grooves with the abradable material. 21. The method as recited in claim 9, wherein revealing the multiple of circumferential grooves occurs via rubbing with a multitude of circumferentially spaced apart blades which extend in a radial direction to the blade tip.