Airfoil prognosis for turbine engines

• US 20070271023A1
• Filed: 05/16/2006
• Published: 11/22/2007
• Est. Priority Date: 05/16/2006
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Morris, Robert J., Tulpule, Sharayu, Littles, Jerrol W.
• Granted Patent: US 7,824,147 B2
• Time in Patent Office: Days
• US Class Current: 701/100
• CPC Class Codes: F01D 21/003 Arrangements for testing or measuring for measuring vibrations G01H
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F05D 2260/96 Preventing, counteracting or reducing vibration or noise
• CPC Class Codes: F05D 2270/11 to prolong engine life
• CPC Class Codes: F05D 2270/708 with comparison tables

Abstract

A method and control for predicting the remaining useful life of an airfoil for a gas turbine engine includes the steps of monitoring conditions of the blade such as flutter, leaning, etc. A measured amount of deflection of the airfoil is compared to tabulated data to predict an expected crack length which is likely causing the deflection, etc. Once a predicted crack length has been identified, the amount of accumulated damage to the airfoil at the crack is monitored and stored. The amount of useful life for the blade can be predicted by compiling the accumulated damage over time. The useful life remaining can be displayed such that flight plans or maintenance schedules for the aircraft can be modified as appropriate.

Claims

1. A turbine engine comprising:

a compressor section, a fan section, and a turbine section, each of said compressor sections and turbine sections having rotors carrying a plurality of blades; and

a sensor associated with at least one of said rotors, said sensor sensing a condition of said blades associated with said at least one of said rotors, said sensor transmitting information to a computer, said computer monitoring information to determine predicted crack length in a blade within said at least one of said rotors, and said damage being utilized to predict an expected life of said blade.

2. The gas turbine engine as set forth in claim 1, wherein said expected life also relies upon operating conditions for the gas turbine engine, and stored damage to the blade over time.

3. The gas turbine engine as set forth in claim 1, wherein said prediction of expected life includes monitoring a deflection in said blade and comparing it to tabulated information at a sensed speed of operation to identify the damage.

4. The gas turbine engine as set forth in claim 1, wherein an immediate failure is predicted should there be a reading associated with one of said blades that exceeds predetermined expected levels.

5. The gas turbine engine as set forth in claim 1, wherein said expected life of said blade is associated with an amount of continued operation of the blade.

6. The gas turbine engine as set forth in claim 5, wherein the amount of continued operation is expressed in mini-sweeps of the blade across a resonance frequency.

7. The gas turbine engine as set forth in claim 5, wherein the amount of continued operation of the blade is expressed in terms of flights.

8. The gas turbine engine as set forth in claim 5, wherein the amount of continued operation of the blade is associated with the type of operation of the gas turbine engine expressed in stress on the blade.

9. The gas turbine engine as set forth in claim 8, wherein a computer stores accumulated damage to the blade over time to reduce a remaining expected life of the blade.

10. The gas turbine engine as set forth in claim 1, wherein the damage is determined based upon a formula.

11. The gas turbine engine as set forth in claim 1, wherein the damage is a predicted crack length in the blade.

12. A method of operating a turbine engine including the steps of:

1) providing a compressor section, a fan section, and a turbine section, each of said compressor sections and turbine sections having rotors carrying a plurality of blades; and

2) sensing a condition of said blades associated with said at least one of said rotors, said sensor transmitting information to a computer, said computer monitoring information to determine predicted damage in a blade within said at least one of said rotors, and said damage being utilized to predict an expected life of said blade.

13. The method as set forth in claim 12, wherein said expected life also relies upon operating conditions for the gas turbine engine, and stored damage to the blade over time.

14. The method as set forth in claim 12, wherein said prediction of expected life includes monitoring a deflection in said blade and comparing it to tabulated information at a sensed speed of operation to identify the damage.

15. The method as set forth in claim 12, wherein an immediate failure is predicted should there be a reading associated with one of said blades that exceeds predetermined expected levels.

16. The method as set forth in claim 12, wherein said expected life of said blade is associated with an amount of continued operation of the blade.

17. The method as set forth in claim 16, wherein the amount of continued operation is expressed in mini-sweeps of the blade across a resonance frequency.

18. The method as set forth in claim 16, wherein the amount of continued operation of the blade is expressed in terms of flights.

19. The method as set forth in claim 16, wherein the amount of continued operation of the blade is associated with the type of operation of the gas turbine engine expressed in stress on the blade.

20. The method as set forth in claim 19, wherein a control stores accumulated damage to the blade over time to reduce a remaining expected life of the blade.

21. The method as set forth in claim 12, wherein the damage is determined based upon a formula.

22. The method as set forth in claim 12, wherein the damage is a predicted crack length.

23. The method as set forth in claim 12, further comprising the step of scheduling the use of said engine as a function of said providing and sensing steps.