The computer - aided analysis of images to assess condition of gas turbine blades

• Autorzy: Pawlak W. , Błachnio J.
• Języki publikacji: EN

Abstrakty

EN

In order to guarantee reliable and safe operation of avionic turbo engine their components and subassemblies are subjected to regular inspections and maintenance. The most frequent reasons for failures of the engines include overheating of materials, thermal fatigue of blades and vanes in the jet subassembly as well as the gas turbine rotor. Failures of that type lead to faulty operation of the engine and sometimes to accidents with disastrous consequences. The decision to have the engine repaired is taken by maintenance personnel that chiefly employ the method of visual inspection with use of a videoscope. However, such examination of turbine components is burdened by a subjective approach. To improve reliability and trustworthiness of the examinations results it is necessary to enable objective and unbiased evaluation of examination results. This paper outlines a non-destructive method that is suitable for evaluation of condition demonstrated by gas turbine blades and is based on digital processing of images acquired from the blade surface in visible light. To enable high clearness of these images the particular attention is paid to the problem of how to provide optimum conditions for investigations and mitigate geometrical distortions of images acquired from maintenance operations. The paper demonstrates that there are relationships between operation lifetime of blades and discoloration of their surfaces due to overheating of the blade material. These relationships are revealed by digital analysis of images acquired for the blade surfaces and expressed as statistical parameter of the first and second order. To improve unambiguity of the analysis results a low-pass filter was applied. It was demonstrated that these relationships are suitable for evaluation how much the status of the blade material microstructure is altered. Results from this study enable formulation of the conclusion that diagnostics of gas turbine blades through computer-aided analysis of images acquired from the blade surfaces may even be possible under field conditions with no downtime of the equipment under tests.

Słowa kluczowe

EN

gas turbine; blades; discoloration; deterioration of microstructure

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2013
• Tom: Vol. 20, No. 3
• Strony: 299--306
• Opis fizyczny: Bibliogr. 12 poz., rys.

Twórcy

autor

Pawlak W.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw, Poland, tel. [phone] fax. [phone]

autor

Błachnio J.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw, Poland tel. [phone] fax. [phone]
• Białystok Technical University Wiejska Street 45C, 15-351 Białystok, Poland

Bibliografia

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• [2] Błachnio, J., Bogdan, M., A non-destructive method to assess condition of gas turbine blades, based on the analysis of blade-surface image, Russian Journal of Non-destructive Testing, Vol. 46, No. 11, pp. 860-866, 2010.
• [3] Błachnio, J., Kułaszka, A., Computer-aided visual inspection of the technical condition of gas turbine blades during their operation period, Journal of KONES, Powertrain and Transport, Vol. 16, No. 3, pp. 23-30, 2009.
• [4] Bogdan, M., Błachnio, J., Derlatka, M., Computer-aided method of diagnostics of gas turbine blades, Acta Mechanica et Automatica, Vol. 3, No. 4, pp. 13-16, 2009.
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