Influence of embedded diagnostic sensors on structure dynamic behavior of composite rotors
Werner Hufenbach*, Marek Fidali**, Paweł Kostka***, Albert Langkamp*** *Technische Universität Dresden, Institut für Leichtbau und Kunststofftechnik, 01062 Dresden, Germany **Politechnika śląska, Katedra Podstaw Konstrukcji Maszyn, ul. Konarskiego 18a, 44-100 Gliwice ***Technische Universität Dresden, Institut für Leichtbau und Kunststofftechnik, 01062 Dresden, Germany
Quarterly No. 3, 2006 pages 14-19
DOI:
keywords: composite rotors, diagnostics, piezoelectric patches, modal analysis
abstract Technological progress in the field of fibre and textile reinforced composites caused that these materials are increasingly used in the process of rotating machinery design including aircraft engines, turbines, etc. Reduction of mass and increase of strength of composite rotor elements by means of optimization of matrix and anisotropic reinforcement properties allows us to decrease dynamical forces and thereby to increase the machinery efficiency. This unique material optimization is impossible in the case of rotors made of classical isotropic materials. The application of the composite rotors with high reliabili-ty demands causes that it is important to evaluate their durability and to investigate phenomena related to the complex material degradation process and to the rotor failures. One of the ways of the failure detection and observation of its evolution is to apply a diagnostic system which use methods based on relations between features of diagnostic signals and the technical state of the machine. Diagnostic signals, e.g. vibroacoustic signals, can be observed and supplied on-line to the diagnostic system. Signal observation requires an application of suitable sensors, which should be mounted as close as possible to the place where the failure can occur. Among of different solutions, a big attention is paid to piezoelectric sensors, which are embedded in composites. Such type of sensors, especially in high-speed rotors, can cause unintended changes of their dynamical properties. In the article, a short overview of requirements for a diagnostic system at the different stages of life of a composite rotor was shown. Exemplary results of numerical modal analysis of a composite rotor disk with embedded piezoelectric sensors was presented. The aim of the experiment was to identify how the size and the number of piezoelectric patches effect on dynamic behavior of the disk at different values of rotational speed.