Éder L. Oliveira, Roberto G. A. da Silva, Nuno M. M Maia, Adolfo G. Marto, Frederico J. Afonso, Afzal Suleman
DOI Number: N/A
Conference number: IFASD-2015-115
This paper aims to improve the data acquisition in experimental aeroelastic analyses using PZT (Lead Zirconate Titanate) excitation and appropriate test parameters definition. High noise levels are usually associated to data acquisition in experimental aeroelastic analyses, leading to spurious roots in the stabilization diagram. Some procedures can be applied to improve the acquisition, for instance by working with the average number of a set of acquisitions. When working with the average number of a set of acquisitions, the noncorrelated inputs (such as noise) tend to disappear. Nevertheless, even when using a broader acquisition set from which to compute an average, it is not possible to obtain a good structural response, due to the poor relationship between signal and noise. Therefore, with the signal/noise relationship enhancement in mind an excitation can be used since it also helps to excite vibration modes that cannot be naturally excited by aerodynamic/turbulence forces. This study has four main investigation fields: (a) to choose the most appropriate type of signal excitation from the available ones; (b) to identify the average number, which improves the structural response when high speeds are the main focus of the wind tunnel test; (c) to define the test parameters aiming to improve the quality of the acquisition data, such as, estimator and window function; and (d) to identify the excitation level, which allows working in the linear structural response. Besides investigating the usage of PZT excitation to improve the data acquisition and showing the importance of an appropriate selection of the test parameters, this work also aims to encourage the development of investigative procedures to enhance data acquisition.