A Wireless Vibration Control Technique for Gas Turbine Blades Using Piezoelectric Plates and Contactless Energy Transfer

Abstract

Gas turbine blade vibrations can give rise to catastrophic failures, and cause a reduction of the blades’ life due to fatigue-related phenomena. Damping is often required to improve performance of bladed disks. Recently, the adoption of piezoelectric elements has received considerable attention by many researchers for potential applicability in different areas of mechanical, aerospace, aeronautical and civil engineering. Furthermore, studies of blades’ vibration-control via piezoelectric plates are beginning to appear. In previous contributions, the authors have proposed a model to control multimode beam vibrations using piezoelectric elements. Analytical results have been validated through comparison with the results of a multi-physics finite elements package (COMSOL), as well as with data available in the literature. Experimental investigations carried out by the authors using a cantilever beam support the proposed theory. The model defines the optimal position of the plates to damp the multimode vibrations. Different loading scenarios where different modes were excited with different percentages were considered [1]. This model has also been extended to a rotating beam, and a finite elements code has been used to obtain the optimal position of the piezo-plates at different rotating speeds ([4]). In this paper the authors report the first results of the experimental investigations performed using a rotating beam. An experimental apparatus has been designed and constructed, including a new wireless power transfer system to eliminate issues associated with the use of slip rings. A Matlab program has been developed to control the system and interpret the data. Also, a laser pointing system has been used to measure the vibrations of a single blade and, thus, the effectiveness of the system. The preliminary results obtained using the newly developed test rig are discussed after presenting the experimental setup and the acquisition system designed and implemented by the authors.