Inductive sensors for blade tip-timing in gas turbines

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The paper reviews features and applications of the upgraded inductive sensor for BTT, which is able to operate in contact with exhaust gases of temperature even as high as 1200 K. The new design includes metal-ceramic housing ensuring proper heat transfer, magnetic circuit containing set of permanent magnets with various magnetic field values and Curie temperatures, completely redesigned windings and current/voltage converter used instead of an electromotive force amplifier. Its principle of operation is based on electro-dynamical interaction and therefore it may be referred as a passive eddy-current sensor. The sensor technique has been demonstrated on four stages of a surplus military turbofan including the high pressure turbine as part of the engine health monitoring system. We present signal samples and review methods used for online processing of time-of-arrival signals when only a limited number of sensors is available.

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Journal of KONBiN

The Journal of Air Force Institute of Technology

Journal Information

CiteScore 2017: 0.21

SCImago Journal Rank (SJR) 2017: 0.163
Source Normalized Impact per Paper (SNIP) 2017: 0.320

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