Monitoring one or more turbine engine rotor blades by correlating measurement data and reference data as a function of time

Patent metadata

Field	Value
Publication number	US-9512736-B2
Application number	US-201213470982-A
Country	US
Kind code	B2
Filing date	May 14, 2012
Priority date	May 14, 2012
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A method is provided for monitoring one or more rotating turbine engine rotor blades using a processing system and a sensor having a measurement field. The method includes steps of: (i) providing measurement data from the sensor as a first of the rotor blades passes through the measurement field; (ii) correlating the measurement data with reference data as a function of time to provide correlation data; and (iii) processing the correlation data to determine a peak correlation value that corresponds to a point in time during the passage of the first of the rotor blades through the measurement field; wherein the correlating and the processing are performed by the processing system.

First claim

What is claimed is:

1. A method for monitoring one or more rotating turbine engine rotor blades using a processing system and a blade position sensor having a measurement field, the method comprising:
receiving measurement data from the blade position sensor as a first of the rotor blades passes through the measurement field;
correlating the measurement data with reference data as a function of time to provide correlation data; and
processing the correlation data to determine a peak correlation value that corresponds to a point in time during the passage of the first of the rotor blades through the measurement field;
determining a time of arrival of the first of the rotor blades at a reference location based on the peak correlation value; and
providing a once per revolution signal based on the time of arrival;
determining a property of the rotor blade using the once per revolution signal;
wherein the correlating and the processing are performed by the processing system.

2. The method of claim 1 , wherein the correlation data includes a plurality of correlation coefficients, and each of the correlation coefficients corresponds to a different point in time during the passage of the first of the rotor blades through the measurement field.

3. The method of claim 2 , wherein the peak correlation value comprises a first of the correlation coefficients having a value that is greater than values of the other correlation coefficients.

4. The method of claim 2 , wherein the processing comprises fitting a mathematical function to the correlation coefficients, and processing the mathematical function to determine a peak correlation coefficient, wherein the peak correlation value comprises the peak correlation coefficient.

5. The method of claim 2 , wherein the correlating is performed using an equation as follows or an equivalent or a derivation thereof:

R
t

=

xy
_

t

-

x
_

t

·

y
_

t

σ

x
t

·

σ

y

t
⁢

,

wherein R is the correlation coefficient, x is a time averaged matrix of a plurality of reference values included in the reference data, y is a time averaged matrix of a plurality of measurement values included in the measurement data, σ x is a standard deviation of x, σ y is a standard deviation of y, and t is a point in time during the passage of the first of the rotor blades through the measurement field.

6. The method of claim 1 , further comprising determining the identity of the first of the rotor blades based on the peak correlation value, wherein each of the rotor blades has a different identity.

7. The method of claim 1 , further comprising:
comparing the peak correlation value to a threshold; and
performing steps as follows where the peak correlation value is less than the threshold:
correlating the measurement data with second reference data as a function of time to provide second correlation data, where the reference data corresponds to the first of the rotor blades, and the second reference data corresponds to an adjacent one of the rotor blades;
processing the second correlation data to determine a second peak correlation value that corresponds to a second point in time during the passage of the first of the rotor blades through the measurement field; and
comparing the second peak correlation value to the threshold.

8. The method of claim 7 , further comprising determining a time of arrival of the first of the rotor blades at a reference location based on the second peak correlation value where the second peak correlation value is greater than the threshold.

9. The method of claim 7 , further comprising determining the identity of the first of the rotor blades based on the second peak correlation value where the second peak correlation value is greater than the threshold, wherein each of the rotor blades has a different identity.

10. The method of claim 9 , further comprising determining presence of at least one of a once per revolution signal dropout and rotor blade jitter based on the identity of the first of the rotor blades.

11. The method of claim 1 , further comprising:
correlating second measurement data for a second of the rotor blades with second reference data as a function of time to provide second correlation data;
processing the second correlation data to determine a second peak correlation value that corresponds to a second point in time during passage of the second of the rotor blades through one of the measurement field and a second measurement field of a second sensor; and
determining a property of one or more of the rotor blades based on the peak correlation value and the second peak correlation value, wherein the property comprises at least one of a modal response magnitude and a nodal diameter.

12. The method of claim 1 , further comprising:
performing the correlating and the processing for a plurality of rotations of the first of the rotor blades around an axis to provide the peak correlation value for each of the rotations; and
determining a property of the first of the rotor blades based on the peak correlation values.

13. The method of claim 12 , wherein the property comprises a time of arrival of the first of the rotor blades at a reference location.

14. The method of claim 12 , wherein the property comprises a chordwise deflection of the first of the rotor blades.

15. The method of claim 12 , wherein the property comprises at least one of a modal response magnitude and a nodal diameter.

16. The method of claim 1 , wherein the processing system is connected to a once per revolution sensor that is discrete from the blade position sensor.

17. A monitoring system for monitoring one or more rotating turbine engine rotor blades, the monitoring system comprising:
a sensor having a measurement field, the sensor configured to be mounted with a turbine engine to provide measurement data as a first of the rotor blades passes through the measurement field; and
a processing system configured to
correlate the measurement data with reference data as a function of time to provide correlation data; and
process the correlation data to determine a peak correlation value that c

Assignees

• Gendrich Charles P
• United Technologies Corp

Inventors

• Gendrich Charles P

Classifications

• F01D17/02 Primary

  Arrangement of sensing elements · CPC title

• F05D2270/334

  Vibration measurements · CPC title

• F01D17/20

  Devices dealing with sensing elements or final actuators or transmitting means between them, e.g. power-assisted (sensing elements alone F01D17/02; final actuators alone F01D17/10) · CPC title

• F05D2270/804

  Optical devices · CPC title

• F05D2270/821

  Displacement measuring means, e.g. inductive · CPC title