Structural Health Monitoring of Turbomachinery using TOA Signal and Expert Software

Abstract

The article portrays a holistic approach to fatigue prevention of turbomachines, based on: 1) rotating state observer of e.g. compressor or turbine blades; 2) tip timing method of indirect, contactless vibration measurement of rotating elements; 3) theoretical basics of sensor working; 4) expert analysis of measurement signal taking into consideration the modal characteristics of rotating state observer, spectra of monitored dynamic phenomena and characteristics of measurement chain; 5) a proactive intervention of the user in fatigue processes – by optimization of operation process of a turbomachine on the basis of the results of diagnostic tests, before damage occurs. The discussed subject matter was illustrated with examples of aviation engines, steam turbines, as well as industrial fans. Upon above 20 years of operational experience in the aviation of the Armed Forces of the Republic of Poland were proved both the purposefulness of a complex analysis of time of arrival (TOA) measurement signal and user intervention in fatigue processes arising out of human mistakes occurring during production, repair, operations, staff training and aviation supervision and user intervention on the stage preceding a fatigue cracking. The obtained results confirmed the purposefulness of using data from structural health monitoring (SHM) to interfere in fatigue processes taking place in antropotechnical device under testing (DUT, in the machine and its environment).