Method for detecting foreign object damage in turbomachinery

摘要

The present invention relates to systems and methods for real-time health monitoring of engines to monitor turbomachinery blades during engine operation and report anomalous behavior and shape of the blades if it occurs, such as damage by FOD. The system includes sensor(s) for obtaining a blade reflection profile from a blade passing by the sensor(s) during a revolution of the rotor in combination with a processor for performing timing calculations and/or fingerprint comparisons with reference data to identify a change in blade fingerprint relative to the reference data, which may indicate blade damage. Such systems can reduce operational costs, enhance safety and improve operational readiness by facilitating condition-based maintenance of engine rotors as opposed to schedule-based solutions. The invention can prevent the needless loss of life and assets caused by undetected minor levels of blade damage that may lead to unexpected catastrophic failure of an engine.

主权项

1. A system for identifying a change in turbomachinery blade fingerprint indicative of blade damage, the system comprising:
one or more sensors for obtaining a signal representing a blade reflection profile from one or more blades passing by the sensors during one or more revolutions of a rotor comprising the blades; at least one computer-readable storage medium in operable communication with the sensors for storing the blade reflection profiles as test data; a processor in operable communication with the storage medium for obtaining corrected test data by: (a) preparing the test data for comparison with reference data; (b) aligning, by blade, the test data with the reference data; (c) differencing the reference data and the test data to obtain residuals; (d) and calculating total error from the residuals to identify a change in blade fingerprint indicative of blade damage; wherein the processor further comprises means for combining or comparing the corrected test data with reference data to identify a change in the blade reflection profile indicative of blade damage, the means comprising: (a) correlating the corrected test data against reference data to obtain a correlation coefficient Rm,n and identify blade offset for one or more blades using the correlation:Rm,n=∑i=1nVal⁢Corr⁡(sigm+i,refn+i) where Corr (sigm+i, refn+i) is a correlation between the corrected test data (sigm+i) and the reference data (refn+i) and is defined as:corr⁡(X,Y)=cov⁡(X,Y)σ⁢⁢x,σ⁢⁢y=E⁡[(X-μ⁢⁢X)⁢(Y-μ⁢⁢y)]σ⁢⁢x,σ⁢⁢y where E is the Expected Value Operator,μx, and μy are the expected values (averages), andσx, σy are the standard deviations of data sets X, and Y respectively, and (b) further correcting the test data for blade offset to obtain blade-offset corrected test data by adjusting blade numbers of the test data to align with blade numbers of the reference data.