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A method for determining a lean blow out condition for a combustor. In an exemplary embodiment, the method includes determining acoustical frequency data for the combustor, determining a combustor flame temperature based on the acoustical frequency data, determining an existing fuel/air ratio in the

A method for determining a lean blow out condition for a combustor. In an exemplary embodiment, the method includes determining acoustical frequency data for the combustor, determining a combustor flame temperature based on the acoustical frequency data, determining an existing fuel/air ratio in the combustor based on the combustor flame temperature, and comparing the existing fuel/ratio to a lean blow out fuel/air ratio. A lean blow out condition for the combustor is indicated when the existing fuel/air ratio is about equal to the lean blow out fuel/air ratio.

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What is claimed is: 1. A method for determining a lean blow out condition for a combustor, the method comprising: determining acoustical frequency data for the combustor in a direction transverse to a flow within the combustor; determining a combustor flame temperature based on said acoustical freq

What is claimed is: 1. A method for determining a lean blow out condition for a combustor, the method comprising: determining acoustical frequency data for the combustor in a direction transverse to a flow within the combustor; determining a combustor flame temperature based on said acoustical frequency data in the direction transverse to the flow within the combustor; determining an existing fuel/air ratio in said combustor based on said combustor flame temperature; and comparing said existing fuel/air ratio to a lean blow out fuel/air ratio, wherein a lean blow out condition for the combustor is indicated when said existing fuel/air ratio is about equal to said lean blow out fuel/air ratio. 2. The method of claim 1, wherein said determining acoustical frequency data further comprises: determining a peak frequency for each of a plurality of combustor cans within an acoustical frequency range; determining a median frequency for said plurality of peak frequencies of said combustor cans; and subtracting said median frequency from said peak frequencies for each of said combustor cans and comparing a resulting differential frequency value therebetween to a calculated first blow out alarm level, said first blow out alarm level corresponding to a frequency less than that of said median frequency. 3. The method of claim 2, wherein said first blow out alarm level is calculated as a function of the value of said median frequency. 4. The method of claim 3, further comprising comparing said differential frequency value to a calculated second blow out alarm level, said second blow out alarm level corresponding to a frequency less than that of said first blow out alarm level. 5. The method of claim 3, further comprising activating a first level alarm whenever a differential frequency value for a given combustor can is less than or equal to said calculated first blow out alarm level. 6. The method of claim 4, further comprising activating a second level alarm whenever a differential frequency value for a given combustor can is less than or equal to said calculated second blow out alarm level. 7. A method for determining a lean blow out condition for a combustor, the method comprising: gathering dynamic pressure data for each of a plurality of combustor cans; determining frequency spectral data from said dynamic pressure data; determining a transverse frequency mode based on the frequency spectral data; determining a peak within the transverse frequency mode for each of said combustor cans, said peak frequencies indicative of an operating temperature within corresponding combustor cans; determining a median frequency for said peak frequencies; subtracting said median frequency from said peak frequencies for each of said combustor cans and comparing a resulting differential frequency value therebetween to a calculated first blow out alarm level, said first blow out alarm level corresponding to a frequency less than that of said median frequency; generating a first alarm level indication for a given combustor can whenever said differential frequency value for said given combustor can is less than or equal to said first blow out alarm level. 8. The method of claim 7, further comprising comparing said differential frequency value to a calculated second blow out alarm level, said second blow out alarm level corresponding to a frequency less than that of said first blow out alarm level. 9. The method of claim 8, further comprising generating a second level alarm indication whenever a differential frequency value for a given combustor can is less than or equal to said calculated second blow out alarm level. 10. The method of claim 7, further comprising confirming that the amplitude of said median frequency meets a threshold level prior to said subtracting said median frequency from said peak frequencies, and prior to generating any first alarm level indications. 11. The method of claim 7, wherein said determining frequency spectral data from said dynamic pressure data further comprises taking a fast Fourier transform of said dynamic pressure data of each can. 12. The method of claim 9, further comprising calculating said first blow out alarm level in accordance with the following expression: description="In-line Formulae" end="lead"FTdiffalm1=FTmarmin+[FTmedfq-Ftmin][( FTmarmax-FTmarmin)/(FTmax-FTmin)];description="In-line Formulae" end="tail" wherein FTmarmin is a constant representing a minimum desired blow out margin, FTmarmax is a constant representing a maximum desired blow out margin, FTmin is a constant representing the frequency corresponding to FTmarmin, FTmax is a constant representing the frequency corresponding to FTmarmax, FTmedfq is the calculated median frequency for the machine (in Hz), and FTdiffalm1 is the calculated allowable blow out margin representing said first blow out alarm level. 13. The method of claim 12, further comprising calculating said second blow out alarm level in accordance with the following expression: description="In-line Formulae" end="lead"FTdiffalm2=FTdiffalm1-Ftdiffdb; description="In-line Formulae" end="tail" where FTdiffdb is a constant representing the margin difference between the first level alarm frequency and the second level alarm frequency. 14. The method of claim 7, wherein said acoustical frequency range is from about 900 Hz to about 1100 Hz. 15. A system for determining a lean blow out condition for a combustor, comprising: a sensing device configured for determining acoustical frequency data for the combustor in a direction transverse to a flow within the combustor; a computing device configured for determining a combustor flame temperature based on said acoustical frequency data in the direction transverse to the flow within the combustor; said computing device further configured for determining an existing fuel/air ratio in said combustor based on said combustor flame temperature, and for comparing said existing fuel/air ratio to a lean blow out fuel/air ratio; wherein a lean blow out condition for the combustor is indicated when said existing fuel/air ratio is about equal to said lean blow out fuel/air ratio. 16. The system of claim 15, wherein said computing device further comprises: a local computing device configured for said determining acoustical frequency data by determining a peak frequency for each of a plurality of combustor cans within an acoustical frequency range, determining a median frequency for said plurality of peak frequencies of said combustor cans, and subtracting said median frequency from said peak frequencies for each of said combustor cans; and a remote computing device in communication with said local computing device, said remote computing device configured to comparing a resulting differential frequency value therebetween to a calculated first blow out alarm level, said first blow out alarm level corresponding to a frequency less than that of said median frequency. 17. The system of claim 16, wherein said first blow out alarm level is calculated as a function of the value of said median frequency. 18. The system of claim 17, wherein said remote computing device is further configured to compare said differential frequency value to a calculated second blow out alarm level, said second blow out alarm level corresponding to a frequency less than that of said first blow out alarm level. 19. The system of claim 17, wherein said remote computing device is further configured to activate a first level alarm whenever a differential frequency value for a given combustor can is less than or equal to said calculated first blow out alarm level. 20. The system of claim 18, wherein said remote computing device is further configured to activate a second level alarm whenever a differential frequency value for a given combustor can is less than or equal to said calculated second blow out alarm level.