Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
SHM BASED ON THE ELECTROMECHANICAL IMPEDANCE FOR DAMAGE DETECTION IN A COMPOSITE SHAFT
Submission Author:
Fernanda Beatriz Aires de Freitas , RN , Brazil
Co-Authors:
Fernanda Beatriz Aires de Freitas, Karina Mayumi Tsuruta, Lucas Rocha, Roberto Mendes Finzi Neto, Aldemir Ap Cavalini Jr, Valder Steffen Jr
Presenter: Fernanda Beatriz Aires de Freitas
doi://10.26678/ABCM.COBEM2019.COB2019-2446
Abstract
The use of composite material in mechanical and aeronautical structures has increased, because of the characteristics of this material, such as low weight/strength ratio and long fatigue life. Despite the advantages of this material, this present distinct damages from structures manufactured with traditional materials, e.g. delamination and fiber rupture. Therefore, it is important to develop methods to detect damages in early stages in order to avoid economic loss and equipment breakdown. In this context, the objective of this paper is to evaluate and improve the robustness of the structural health monitoring method based on electromechanical impedance (ISHM) to detect damages on a composite rotor hollow shaft considering the temperature variation, since this methodology is influenced by such variable. This non-destructive technique uses the property of the piezoelectric transducers, acting as sensors and actuators. For the experiment, a composite shaft (532mm length, 17mm diameter and 1.35mm thickness) was used. Three piezoelectric transducers (each one with four piezoelectric patches electric connected in parallel) were bonded on the shaft surface. To simulate the damage, a steel nut was attached to the shaft. Measurements were performed before and after the damage at room temperature and inside a thermal chamber with controlled temperature (5°C, 10 °C, 15 °C, 20 ºC, 25 ºC, 30 ºC, 35°C, 40 ºC and 45°C). To quantify the damage, a damage index was used. Furthermore, an optimization method based on hybrid optimization was developed to minimize the temperature effect on these signatures, preventing false positives.
Keywords
composite shafts, ISHM, electromechanical impedance, damage metrics
