Monitoring health of a combustion dynamics sensing system

1. A method for monitoring a health of a combustion dynamics sensing system comprising:

monitoring respective dynamic conditions of at least two combustor cans of a can annular combustor of a gas turbine engine with respective dynamic condition sensors associated with each of the cans;

determining relationships between the respective dynamic conditions of adjacent cans;

establishing a baseline relationship for each relationship between the respective dynamic conditions of adjacent cans; and

identifying a variance of a relationship between the respective dynamic conditions of adjacent cans from the respective baseline relationship indicative of a degraded signal quality provided by a dynamic condition sensor associated with at least one of the cans.

2. The method of claim 1 , wherein the relationship comprises a phase relationship between phase angle values of the respective dynamic conditions.

3. The method of claim 2 , wherein the phase relationship comprises an out-of-phase relationship.

4. The method of claim 3 , wherein the out-of-phase relationship comprises a phase angle difference of about one hundred and eighty degrees.

5. The method of claim 4 . wherein the variance comprises a phase angle difference of more than about 10 degrees away from one hundred and eighty degrees.

6. The method of claim 4 , wherein the variance comprises a phase angle difference of more than about 20 degrees away from one hundred and eighty degrees.

7. The method of claim 4 , wherein the variance comprises a phase angle difference of more than about 30 degrees away from one hundred and eighty degrees.

8. The method of claim 1 , further comprising monitoring the dynamic conditions within a frequency range associated with a peak dynamic frequency condition.

9. The method of claim 8 , wherein the frequency range extends from about 120 Hertz to about 220 Hertz and about 400 Hertz to about 500 Hertz

10. The method of claim 8 , wherein the frequency range extends from about 400 Hertz to about 500 Hertz.

11. The method of claim 1 , wherein the degraded signal quality is indicative of a water contaminated damping tube associated with at least one of the cans.

12. The method of claim 1 , wherein the degraded signal quality is indicative of a failure of a signal processing element associated with at least one of the dynamic condition sensors.

13. A system for monitonng a health of a combustion dynamics sensing system of a can annular gas turbine engine comprising;

a plurality of sensors for sensing respective dynamic operating conditions of cans of a can annular combustor of a gas turbine engine;

a processor receiving respective sensed dynamic condition signals from the plurality of sensors; and

programmed logic operable with the processor for monitoring respective dynamic operating conditions of cans, determining relationships between the dynamic operating conditions of adjacent cans, establishing a baseline relationship for each relationship between dynamic operating conditions of adjacent cans, and for identifying a variance of a relationship between the respective dynamic conditions of adjacent cans from the respective baseline relationship indicative of a degraded signal quality provided by a sensor associated with at least one of the cans.

14. A method for monitoring a health of a combustion dynamics sensing system comprising:

obtaining raw signals responsive to combustion in a plurality of cans of a can annular combustor of a gas turbine engine;

performing a transformation operation on the raw signals to generate respective phase information corresponding to each signal;

determining phase relationships between respective adjacent cans;

establishing a baseline relationship for each phase relationships between respective adiacent cans; and

comparing the phase relationships to respective baseline phase relationships for each signal in a selected range of frequencies to evaluate a signal reliability of the raw signals.

15. The method of claim 14 , wherein the transformation operation comprises a Fourier transform.

16. The method of claim 14 , wherein the raw signals comprise pressure sensor signals.

17. The method of claim 14 , wherein the raw signals comprise optical sensor signals.

18. The method of claim 14 , wherein the raw signals comprise acoustic sensor signals.

19. The method of claim 14 , wherein the raw signals comprise electromagnetic sensor signals.