Abstract: A method dynamically reconstructing a stress and strain field of a turbine blade includes providing a set of response measurements from at least one location on a turbine blade, band-pass filtering the set of response measurements based on an upper frequency limit and a lower frequency limit, determining an upper envelope and a lower envelope of the set of response measurements from local minima and local maxima of the set of response measurements, calculating a candidate intrinsic mode function (IMF) from the upper envelope and the lower envelope of the set of response measurements, providing an N×N mode shape matrix for the turbine blade, where N is the number of degrees of freedom of the turbine blade, when the candidate IMF is an actual IMF, and calculating a response for another location on the turbine blade from the actual IMF and mode shapes in the mode shape matrix.

Abstract: A method of calibrating transceiver positions inside an acoustic pyrometry measuring vessel that contains a plurality of transceivers, includes determining (40) a speed of sound in the acoustic pyrometry measuring vessel from a temperature and gas composition of a gas inside the acoustic pyrometry measuring vessel, acquiring (41) time-of-flight (TOFs) ?ti,j measurements from a plurality of pairs i,j of transceivers inside the acoustic pyrometry measuring vessel, estimating (42) a radius of the acoustic pyrometry measuring vessel from an average of the acquired TOF measurements, and using (43) an estimated radius of the acoustic pyrometry measuring vessel to estimate errors ??j of displacement angles of the transceivers.

Abstract: The state of a flame in a gas turbine engine combustor is acoustically monitored using a dynamic pressure sensor within the combustor. A spectral pattern of a dynamic pressure sensor output signal from the sensor is compared with a characteristic frequency pattern that includes information about an acoustic pattern of the flame and information about acoustic signal canceling due to reflections within the combustor. The spectral pattern may also be compared with a characteristic frequency pattern including information about a flame-out condition in the combustor.

Abstract: An acoustic signal traversing a hot gas is sampled at a source and a receiver and is represented in overlapping windows that maximize useable signal content. Samples in each window are processed to represented in different sparsified bins in the frequency domain. Determining a signal delay between the source and the receiver from a summation of maximum smoothed coherence transform cross-correlation values of different data windows wherein a sparseness of a mean smoothed coherence transform cross-correlation of windows is maximized. Determining a set of delay times wherein outliers are deleted to estimate a time of flight from which a temperature of the hot gas is calculated.

Abstract: The state of a flame in a subject combustor of a gas turbine engine is acoustically monitored using a dynamic pressure sensor within the subject combustor and one or more additional sensors in nearby combustors. Dynamic pressure sensor output signals from the sensors are cross correlated to identify acoustic oscillations generated by a flame in the subject combustor and received by the sensors. The cross correlation may be constrained by a maximum time delay between correlated components of the signals, based on physical characteristics.

Abstract: The flame status of a group of gas turbine combustors is acoustically monitored using dynamic pressure sensors within the combustor. Dynamic pressure sensor output signals are received from the sensors and processed to determine flame status. The signals are processed both by performing a correlation analysis within each combustor and by applying a wavelet-based flame detection algorithm to each output signal. A flame is determined to be present based on the correlation analysis and the wavelet-based flame detection algorithm. The wavelet-based flame detection algorithm is chosen based on whether the gas turbine combustors are in an ignition phase or a monitoring phase.

Abstract: The state of a flame in a gas turbine combustor is acoustically monitored using a single dynamic pressure sensor within the combustor. A dynamic pressure sensor output signal is received from the single sensor and is processed to determine a flame status. The signal is processed by performing an autocorrelation operation to identify time-separated portions of the signal and to determine that the time-separated portions of the signal include portions indicative of acoustic oscillations emitted by the flame in the gas turbine engine combustor and received directly by the single acoustic sensor, and portions indicative of reflections.

Abstract: The flame status of a group of gas turbine combustors is acoustically monitored using dynamic pressure sensors within the combustor. Dynamic pressure sensor output signals are received from the sensors and processed to determine flame status. The signals are processed both by performing a correlation analysis within each combustor and by applying a wavelet-based flame detection algorithm to each output signal. A flame is determined to be present based on the correlation analysis and the wavelet-based flame detection algorithm. The wavelet-based flame detection algorithm is chosen based on whether the gas turbine combustors are in an ignition phase or a monitoring phase.

Abstract: A method and apparatus for operating a gas turbine engine including determining a temperature of a working gas at a predetermined axial location within the engine. An acoustic signal is encoded with a distinct signature defined by a set of predetermined frequencies transmitted as a non-broadband signal. Acoustic signals are transmitted from an acoustic transmitter located at a predetermined axial location along the flow path of the gas turbine engine. A received signal is compared to one or more transmitted signals to identify a similarity of the received signal to a transmitted signal to identify a transmission time for the received signal. A time-of-flight is determined for the signal and the time-of-flight for the signal is processed to determine a temperature in a region of the predetermined axial location.

Abstract: A gas turbine includes first and second parts having outer surfaces located adjacent to each other to create an interface where wear occurs. A wear probe is provided for monitoring wear of the outer surface of the first part, and includes an optical guide having first and second ends, wherein the first end is configured to be located flush with the outer surface of the first part. A fiber bundle includes first and second ends, the first end being located proximate to the second end of the optical guide. The fiber bundle includes a transmit fiber bundle comprising a first plurality of optical fibers coupled to a light source, and a receive fiber bundle coupled to a light detector and configured to detect reflected light. A processor is configured to determine a length of the optical guide based on the detected reflected light.

Abstract: The state of a flame in a gas turbine combustor is acoustically monitored using a single dynamic pressure sensor within the combustor. A dynamic pressure sensor output signal is received from the single sensor and is processed to determine a flame status. The signal is processed by performing an autocorrelation operation to identify time-separated portions of the signal and to determine that the time-separated portions of the signal include portions indicative of acoustic oscillations emitted by the flame in the gas turbine engine combustor and received directly by the single acoustic sensor, and portions indicative of reflections.

Abstract: The state of a flame in a subject combustor of a gas turbine engine is acoustically monitored using a dynamic pressure sensor within the subject combustor and one or more additional sensors in nearby combustors. Dynamic pressure sensor output signals from the sensors are cross correlated to identify acoustic oscillations generated by a flame in the subject combustor and received by the sensors. The cross correlation may be constrained by a maximum time delay between correlated components of the signals, based on physical characteristics.

Abstract: A method and apparatus for operating a gas turbine engine including determining a temperature of a working gas at a predetermined axial location within the engine. An acoustic signal is encoded with a distinct signature defined by a set of predetermined frequencies transmitted as a non-broadband signal. Acoustic signals are transmitted from an acoustic transmitter located at a predetermined axial location along the flow path of the gas turbine engine. A received signal is compared to one or more transmitted signals to identify a similarity of the received signal to a transmitted signal to identify a transmission time for the received signal. A time-of-flight is determined for the signal and the time-of-flight for the signal is processed to determine a temperature in a region of the predetermined axial location.

Abstract: The state of a flame in a gas turbine engine combustor is acoustically monitored using a dynamic pressure sensor within the combustor. A spectral pattern of a dynamic pressure sensor output signal from the sensor is compared with a characteristic frequency pattern that includes information about an acoustic pattern of the flame and information about acoustic signal canceling due to reflections within the combustor. The spectral pattern may also be compared with a characteristic frequency pattern including information about a flame-out condition in the combustor.

Abstract: A method dynamically reconstructing a stress and strain field of a turbine blade includes providing a set of response measurements from at least one location on a turbine blade, band-pass filtering the set of response measurements based on an upper frequency limit and a lower frequency limit, determining an upper envelope and a lower envelope of the set of response measurements from local minima and local maxima of the set of response measurements, calculating a candidate intrinsic mode function (IMF) from the upper envelope and the lower envelope of the set of response measurements, providing an N×N mode shape matrix for the turbine blade, where N is the number of degrees of freedom of the turbine blade, when the candidate IMF is an actual IMF, and calculating a response for another location on the turbine blade from the actual IMF and mode shapes in the mode shape matrix.

Abstract: An acoustic signal traversing a hot gas is sampled at a source and a receiver and is represented in overlapping windows that maximize useable signal content. Samples in each window are processed to represented in different sparsified bins in the frequency domain. Determining a signal delay between the source and the receiver from a summation of maximum smoothed coherence transform cross-correlation values of different data windows wherein a sparseness of a mean smoothed coherence transform cross-correlation of windows is maximized. Determining a set of delay times wherein outliers are deleted to estimate a time of flight from which a temperature of the hot gas is calculated.

Abstract: A gas turbine includes first and second parts having outer surfaces located adjacent to each other to create an interface where wear occurs. A wear probe is provided for monitoring wear of the outer surface of the first part, and includes an optical guide having first and second ends, wherein the first end is configured to be located flush with the outer surface of the first part. A fiber bundle includes first and second ends, the first end being located proximate to the second end of the optical guide. The fiber bundle includes a transmit fiber bundle comprising a first plurality of optical fibers coupled to a light source, and a receive fiber bundle coupled to a light detector and configured to detect reflected light. A processor is configured to determine a length of the optical guide based on the detected reflected light.

Abstract: A diagnostic system and method for monitoring operating conditions of turbine machine components (18, 19, 22, 23) that comprise one or more non-contact sensors (24, 31) that detect an operating condition of a turbine component (18, 19, 22, 23) over a defined region of the component. In addition, point sensors (50) are provided that detect and monitor the same operating condition within the defined region. Data generated from the point sensor (50) is used to calibrate the non-contact sensor (24, 31) and the data generated by the non-contact sensor (24, 31).

Abstract: A diagnostic system and method for monitoring operating conditions of turbine machine components (18, 19, 22, 23) that comprise one or more non-contact sensors (24, 31) that detect an operating condition of a turbine component (18, 19, 22, 23) over a defined region of the component. In addition, point sensors (50) are provided that detect and monitor the same operating condition within the defined region. Data generated from the point sensor (50) is used to calibrate the non-contact sensor (24, 31) and the data generated by the non-contact sensor (24, 31).

Abstract: A system and method for determining the condition of one or more parameters of a valve, e.g., particularly a check valve in a fluid carrying pipe, by monitoring fluid turbulence downstream of the valve. An ultrasonic transmitter-receiver transducer pair provides a signal modulated by the fluid turbulence, which signal is demodulated and processed to obtain a signature or other signal indicative of the valve condition. The processes signature signal may additionally be compared with a measure of flow rate determined just upstream from the valve. By operating the ultrasonic system at high frequency and using appropriate detecting circuitry, low frequency interference from mechanical shocks and vibrations is avoided, yielding a reliable detection of the flow turbulence caused by the valve.